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IAU Colloquium 193 - A personal view
NASA Astrophysics Data System (ADS)
Kawaler, S. D.
One of the more famous (or infamous) films of all time was Akira Kurosawa's Rashomon. In this film, Kurosawa tells the story of a terrible crime... and tells it four times. Each telling is from the perspective of a different character. In this masterful film the viewer is never quite sure what really happened; each of the protagonists tells the same tale but with their own personal interpretation. Summarizing a week spent in the cold clear air of wintertime Christchurch (and that was inside the lecture hall) is indeed a daunting task. Each of us who was fortunate enough to have attended IAU Colloquium 193 came away from the meeting with our own impressions, highlights, and revelations. So by writing now about by own reflections, my goal is to rekindle yours, rather than persuade you that my summary is any more authoritative than one you might write. Of course, those of you reading this who were not at the conference are stuck with this summary - but by reading the preceding papers in this volume you, too, can have a sense of the variety we enjoyed. Below, I start with a survey of some broad themes that emerged. A few results were of the `Gee Whiz' variety, and are outlined in the next section. A few old problems were revisited by several participants, and also some new problems have emerged, and I outline them next. After a nod to two very special participants in this Colloquium, I conclude with some final thoughts.
Proceedings of the eighth international colloquium on ultraviolet and x-ray spectroscopy of astrophysical and laboratory plasmas (IAU colloquium 86)
Not Available
This volume represents the Proceedings of the Eighth International Colloquium on Ultraviolet and X-Ray Spectroscopy of Astrophysical and Laboratory Plasmas. The aim of this series of colloquia has been to bring together workers in the fields of astrophysical spectroscopy, laboratory spectroscopy and atomic physics in order to exchange ideas and results on problems which are common to these different disciplines. In addition to the presented papers there was a poster paper session. (WRF)
Plasma Colloquium Travel Grant Program
Hazeltine, R.D.
OAK B188 Plasma Colloquium Travel Grant Program. The purpose of the Travel Grant Program is to increase the awareness of plasma research. The new results and techniques of plasma research in fusion plasmas, plasma processing space plasmas, basic plasma science, etc, have broad applicability throughout science. The benefits of these results are limited by the relatively low awareness and appreciation of plasma research in the larger scientific community. Whereas spontaneous interactions between plasma scientists and other scientists are useful, a focused effort in education and outreach to other scientists is efficient and is needed. The academic scientific community is the initial focus of this effort, since that permits access to a broad cross-section of scientists and future scientists including undergraduates, graduate students, faculty, and research staff.
COSPAR, IAU, LSI Colloquium on Lunar Dynamics and Observational Coordinate Systems: Revised abstracts
NASA Technical Reports Server (NTRS)
Moutsoulas, M. (Editor)
The proceedings of a colloquium on lunar dynamics and observational coordinate systems are presented. Discussions were held on the establishment of a fundamental reference system and on the lunar ephemerides. Abstracts of the subjects discussed at the meeting are submitted. Some of the topics discussed are: (1) coordinates of the Apollo retroreflectors, (2) determination of lunar baselines, (3) numerical series for the variations of lunar coordinates, (4) fundamental craters for establishing a lunar coordinate system, and (5) composite lunar gravity fields.
FOREWORD: 4th International Colloquium on Atomic Spectra and Oscillator Strengths for Astrophysical and Laboratory Plasmas
NASA Astrophysics Data System (ADS)
Leckrone, David S.; Sugar, Jack
common. The series has also demonstrated that the dialogue between "users" and "providers" of atomic data is a two-way conversation, with atomic physicists beginning to view astrophysical and laboratory plasmas as unique sources of new information about the structure of complex atomic species. The fifth International Colloquium on Atomic Spectra and Oscillator Strengths for Astrophysical and Laboratory Plasmas is scheduled to take place in Meudon, France in 1995.
FOREWORD: The 5th International Colloquium on Atomic Spectra and Oscillator Strengths for Astrophysical and Laboratory Plasmas
NASA Astrophysics Data System (ADS)
Tchang-Brillet, Wad Lydia; Wyart, Jean-François; Zeippen, Claude
The 5th International Colloquium on Atomic Spectra and Oscillator Strengths for Astrophysical and Laboratory Plasmas was held in Meudon, France, from August 28 to 31 1995. It was the fifth in a series started by the Atomic Spectroscopic Group at the University of Lund, Sweden, in 1983. Then followed the meetings in Toledo, USA, Amsterdam, The Nether- lands and Gaithersburg, USA, with a three year period. The original title of the series ended with "... for Astrophysics and Fusion Research" and became more general with the 4th colloquium in Gaithersburg. The purpose of the present meeting was, in line with tradition, to bring together "producers" and "users" of atomic data so as to ensure optimal coordination. Atomic physicists who study the structure of atoms and their radiative and collisional properties were invited to explain the development of their work, emphasizing the possibilities of producing precise transition wavelengths and relative line intensities. Astrophysicists and laboratory plasma physicists were invited to review their present research interests and the context in which atomic data are needed. The number of participants was about 70 for the first three meetings, then exploded to 170 at Gaithersburg. About 140 participants, coming from 13 countries, attended the colloquium in Meudon. This large gathering was partly due to a number of participants from Eastern Europe larger than in the past, and it certainly showed a steady interest for interdisciplinary exchanges between different communities of scientists. This volume includes all the invited papers given at the conference and, in the appendix, practical information on access to some databases. All invited speakers presented their talks aiming at good communication between scientists from different backgrounds. A separate bound volume containing extended abstracts of the poster papers has been published by the Publications de l'Observatoire de Paris, (Meudon 1996), under the responsibility of
NASA Astrophysics Data System (ADS)
Hohenkerk, Catherine
SOFA (Standards Of Fundamental Astronomy) software is a resource for astronomers, provided via IAU Division 1. The library contains the latest (IAU approved) algorithms for Earth attitude - precession, nutation, Earth rotation angle, sidereal time. Does your software use time? Need to convert between, for example UTC, UT1, or TT? Then SOFA has all you need. Using SOFA you can convert between FK5 and Hipparcos positions, between geodetic and geocentric coordinates, as well as conversions between the BCRS (ICRS) or J2000.0 and both the celestial and terrestrial reference systems. All routines, Fortran or ANSI C, are available as source code or as part of a library. Visit our website at http://www.iausofa.org/ to find out more and download what you need.
Final Report: Plasma Colloquium Travel Grant Program, September 15, 1997 - September 14, 1998
Hazeltine, Richard D.
The purpose of the Travel Grant Program is to increase the awareness of plasma research. The new results and techniques of plasma research in fusion plasmas, plasma processing space plasmas, basic plasma science, etc, have broad applicability throughout science. The benefits of these results are limited by the relatively low awareness and appreciation of plasma research in the larger scientific community. Whereas spontaneous interactions between plasma scientists and other scientists are useful, a focused effort in education and outreach to other scientists is efficient and is needed. The academic scientific community is the initial focus of this effort, since that permits access to a broad cross-section of scientists and future scientists including undergraduates, graduate students, faculty, and research staff.
Colloquium: Nonlinear collective interactions in quantum plasmas with degenerate electron fluids
Shukla, P. K.; Eliasson, B.
The current understanding of some important nonlinear collective processes in quantum plasmas with degenerate electrons is presented. After reviewing the basic properties of quantum plasmas, model equations (e.g., the quantum hydrodynamic and effective nonlinear Schroedinger-Poisson equations) are presented that describe collective nonlinear phenomena at nanoscales. The effects of the electron degeneracy arise due to Heisenberg's uncertainty principle and Pauli's exclusion principle for overlapping electron wave functions that result in tunneling of electrons and the electron degeneracy pressure. Since electrons are Fermions (spin-1/2 quantum particles), there also appears an electron spin current and a spin force acting on electrons due to the Bohr magnetization. The quantum effects produce new aspects of electrostatic (ES) and electromagnetic (EM) waves in a quantum plasma that are summarized in here. Furthermore, nonlinear features of ES ion waves and electron plasma oscillations are discussed, as well as the trapping of intense EM waves in quantum electron-density cavities. Specifically, simulation studies of the coupled nonlinear Schroedinger and Poisson equations reveal the formation and dynamics of localized ES structures at nanoscales in a quantum plasma. The effect of an external magnetic field on the plasma wave spectra and develop quantum magnetohydrodynamic equations are also discussed. The results are useful for understanding numerous collective phenomena in quantum plasmas, such as those in compact astrophysical objects (e.g., the cores of white dwarf stars and giant planets), as well as in plasma-assisted nanotechnology (e.g., quantum diodes, quantum free-electron lasers, nanophotonics and nanoplasmonics, metallic nanostructures, thin metal films, semiconductor quantum wells, and quantum dots, etc.), and in the next generation of intense laser-solid density plasma interaction experiments relevant for fast ignition in inertial confinement fusion
Tenth International Colloquium on UV and X-Ray Spectroscopy of Astrophysical and Laboratory Plasmas
NASA Astrophysics Data System (ADS)
Silver, Eric H.; Kahn, Steven M.
UV and X-ray spectroscopy of astrophysical and laboratory plasmas draws interest from many disciplines. Contributions from international specialists are collected together in this book from a timely recent conference. In astrophysics, the Hubble Space Telescope, Astro 1 and ROSAT observatories are now providing UV and X-ray spectra and images of cosmic sources in unprecedented detail, while the Yohkoh mission recently collected superb data on the solar corona. In the laboratory, the development of ion-trap facilities and novel laser experiments are providing vital new data on high temperature plasmas. Recent innovations in the technology of spectroscopic instrumentation are discussed. These papers constitute an excellent up-to-date review of developments in short-wavelength spectroscopy and offer a solid introduction to its theoretical and experimental foundations. These proceedings give an up-to-date review of developments in short-wavelength spectroscopy and offer a solid introduction to its theoretical and experimental foundations. Various speakers presented some of the first results from the high resolution spectrograph on the Hubble Space Telescope, the high sensitivity far ultraviolet and X-ray spectrometers of the ASTRO 1 Observatory, the imaging X-ray spectrometer on the ROSAT Observatory, and the high resolution solar X-ray spectrometer on Yohkoh. The development of ion trap devices had brought about a revolution in laboratory investigations of atomic processes in highly charged atoms. X-ray laser experiments had not only yielded considerable insight into electron ion interactions in hot dense plasmas, but also demonstrated the versatility of laser plasmas as laboratory X-ray sources. Such measurements also motivated and led to refinements in the development of large-scale atomic and molecular codes. On the instrumental side, the design and development of the next series of very powerful short wavelength observatories had generated a large number of
The International Colloquium on Atomic Spectra and Oscillator Strengths for Astrophysical and Laboratory Plasmas
NASA Technical Reports Server (NTRS)
Sugar, J.; Leckrone, D.
This was the fourth in a series of colloquia begun at the University of Lund, Sweden in 1983 and subsequently held in Toledo, Ohio and Amsterdam, The Netherlands. The purpose of these meetings is to provide an international forum for communication between major users of atomic spectroscopic data and the providers of these data. These data include atomic wavelengths, line shapes, energy levels, lifetimes, and oscillator strengths. Speakers were selected from a wide variety of disciplines including astrophysics, laboratory plasma research, spectrochemistry, and theoretical and experimental atomic physics.
NASA Technical Reports Server (NTRS)
Simon, J. L.
Every three years the IAU/IAG/COSPAR Working Group on Cartographic Coordinates and Rotational Elements of the Planets and Satellites revises tables giving the directions of the north poles rotation and the prime meridians of the planets, satellites, and asteriods and also tables of their sizes and shapes.
The IAU Office for Astronomy Outreach
NASA Astrophysics Data System (ADS)
Cheung, Sze Leung
The International Astronomical Union (IAU) Office for Astronomy Outreach (OAO) is an IAU new office hosted at National Astronomical Observatory of Japan (NAOJ) at Tokyo. After the International Year of Astronomy 2009, IAU decided to establish the OAO to coordinate the international astronomical outreach efforts. The IAU Office for Astronomy Outreach (OAO) is IAU's hub for coordinating its public outreach activities around the world. The aim is to build networks to support and disseminate information to the amateur astronomy and public outreach communities, and to ultimately make it easier for the public to access information about our Universe.
The IAU Office of Astronomy for Development
NASA Astrophysics Data System (ADS)
Govender, Kevin
On 16 April 2011 the IAU's Office of Astronomy for Development (OAD) was launched jointly by the President of the IAU and the South African Minister of Science and Technology, at the South African Astronomical Observatory in Cape Town. This OAD was set up to realise the IAU's strategic plan which aims to use astronomy as a tool for development. Communicating astronomy with the public is one of the OAD's focus areas.
Presentation of the IAU National Outreach Contact
NASA Astrophysics Data System (ADS)
Montesinos, B.; Belmonte, J. A.
The International Astronomical Union (IAU) has created the Office of for Astronomy Outreach (IAU-OAO). Its mission is to promote and coordinate the activities of astronomy outreach worldwide. For this purpose, the IAU-OAO has established a network of partners based on what was established to celebrate the International Year of Astronomy (IYA2009). The nodes of this new network (IAU National Outreach Contacts, IAU-NOC) act as National Contact Points (NCPs) statewide and their mission is to contribute to the implementation of the objectives of the IAU-OAO. The commitment of the NOC is a three-year renewal charge. The replacement or the renewal will occur during the celebration of the relevant General Assembly of the IAU. In the case of Spain, the Comisión Nacional de Astronomía (CNA) decided to appoint a Vice-NOC and NOC and the relay will occur during the next IAU General Assembly to be held in Honolulu in August 2015.
Eleventh NASTRAN User's Colloquium
NASA Technical Reports Server (NTRS)
NASTRAN (NASA STRUCTURAL ANALYSIS) is a large, comprehensive, nonproprietary, general purpose finite element computer code for structural analysis which was developed under NASA sponsorship. The Eleventh Colloquium provides some comprehensive general papers on the application of finite element methods in engineering, comparisons with other approaches, unique applications, pre- and post-processing or auxiliary programs, and new methods of analysis with NASTRAN.
Colloquium Participants Speak.
ERIC Educational Resources Information Center
Chafe, Joanne
Presents a summary and interpretation of responses from the participants of the Catholic-Jewish Colloquium. The participants reflect on a number of issues including the changing nature of the relationship between Judaism and Christianity, the rationale and impact of this changed relationship, the particular elements involved in the…
IAU Public Astronomical Organisations Network
NASA Astrophysics Data System (ADS)
Canas, Lina; Cheung, Sze Leung
The Office for Astronomy Outreach has devoted intensive means to create and support a global network of public astronomical organisations around the world. Focused on bringing established and newly formed amateur astronomy organizations together, providing communications channels and platforms for disseminating news to the global community and the sharing of best practices and resources among these associations around the world. In establishing the importance that these organizations have for the dissemination of activities globally and acting as key participants in IAU various campaigns social media has played a key role in keeping this network engaged and connected. Here we discuss the implementation process of maintaining this extensive network, the processing and gathering of information and the interactions between local active members at a national and international level.
SOFA, an IAU service for the future
NASA Astrophysics Data System (ADS)
Hohenkerk, Catherine
Standards of Fundamental Astronomy (SOFA) is an International Astronomical Union (IAU) service that provides accessible and authoritative algorithms and procedures that implement standard models used in fundamental astronomy. SOFA consists of a dedicated web site from which the SOFA Software Collections (Fortran and ANSI C) may be downloaded and a Board t hat provides and checks the material. This talk highlights SOFA's development, what it provides users and the IAU, as well as indicating issues that may arise in the future.
FOREWORD: The 9th International Colloquium on Atomic Spectra and Oscillator Strengths for Astrophysical and Laboratory Plasmas (ASOS 9)
NASA Astrophysics Data System (ADS)
Wahlgren, Glenn M.; Wiese, Wolfgang L.; Beiersdorfer, Peter
For the first time since its inaugural meeting in Lund in 1983, the triennial international conference on Atomic Spectroscopy and Oscillator Strengths for Astrophysical and Laboratory Plasmas (ASOS) returned to Lund, Sweden. Lund has been a home to atomic spectroscopy since the time of Janne Rydberg, and included the pioneering work in laboratory and solar spectroscopy of Bengt Edlén, who presented the initial ASOS talk in 1983. The ninth ASOS was hosted by the Lund Observatory and the Physics Department of Lund University during from 8 to 10 August 2007 and was attended by nearly 100 registrants. An encouraging sign for the field was the number of young researchers in attendance. This volume contains the submitted contributions from the poster presentations of the conference, and represents approximately forty percent of the presented posters. A complementary volume of Physica Scripta provides the written transactions of the ASOS9 invited presentations. With these two volumes the character of ASOS9 is more fully evident, and they serve as a review of the state of atomic spectroscopy for spectrum analysis and the determination of oscillator strengths and their applications. The goal of ASOS is to be a forum for atomic spectroscopy where both the providers and users of atomic data, which includes wavelengths, energy levels, lifetimes, oscillator strengths, and line shape parameters, can meet to discuss recent advances in experimental and theoretical techniques and their application to understanding the physical processes that are responsible for producing observed spectra. The applications mainly originate from the fields of astrophysics and plasma physics, the latter including fusion energy and lighting research. As a part of ASOS9 we were honored to celebrate the retirement of Professor Sveneric Johansson. At a special session on the spectroscopy of iron, which was conducted in his honor, he presented his insights into the Fe II term system and his most recent
Improvement of the IAU 2000 precession model
NASA Astrophysics Data System (ADS)
Capitaine, N.; Wallace, P. T.; Chapront, J.
The IAU 2000 precession consists of the IAU 1976 ecliptic precession (Lieske et al. [CITE], A&A, 58, 1) and the precession part of the IAU 2000A equator adopted by IAU 2000 Resolution B1.6 (Mathews et al. [CITE], J. Geophys. Res., 107, B4, 10.1029/2001JB000390). In this paper we provide a range of new expressions as possible replacements for the IAU 2000 precession. The new expressions are based upon the so-called P03 solution of Capitaine et al. ([CITE], A&A, 412, 567) for the equator and the ecliptic. In addition an improved model for the precession of the equator is discussed. This improved solution was obtained in exactly the same way as P03 but using a refined model for the contributions of the non-rigid Earth (Mathews [CITE], private communication) and revised integration constants for the precession rates resulting from fits to the most recent VLBI data. The paper reports on the procedure that was used for improving the P03 solution and on the comparisons of this solution with the MHB 2000, IAU 2000 and P03 solutions. It also discusses the choices for the solution to be put forward as a replacement for IAU 2000. We concluded that the existing VLBI data were insufficient to provide convincing evidence that the improved solutions would deliver better accuracy than the existing P03 solution, and we recommend retaining P03 as the replacement for IAU 2000. P03, which unlike the IAU 2000 precession is dynamically consistent, has the advantage of already having been used experimentally by a number of groups; the model is recalled in Tables [see full text]- [see full text]. Due to the strong dependence of the precession expressions on the precession rates and of the precession in longitude (or equivalently the celestial CIP X coordinate) on the J2 rate model, we also provide a parameterized P04 solution for these quantities as functions of those parameters. The expressions include the quantities to be used in both the equinox-based and CIO-based (i.e. referred to
Second International Colloquium on Mars: Abstracts for a colloquium. [bibliography
NASA Technical Reports Server (NTRS)
Abstracts of 110 papers relating to investigations of the planet Mars and intended for consideration at the colloquium are presented. Entries are arranged alphabetically according to the author's name.
Proceedings of Colloquium 110 of the International Astronomical Union on Library and Information Services in Astronomy
NASA Astrophysics Data System (ADS)
Wilkins, George A.; Stevens-Rayburn, Sarah
This report provides an overview of the presentations and summaries of discussions at IAU Colloquium 110, which was held in Washington, D.C., on 26-30 July 1988 and at the Goddard Space Flight Center on 1 August 1988. The topics included: the publication and acquisition of books and journals; searching for astronomical information; the handling and use of special-format materials; conservation; archiving of unpublished documents; uses of computers in libraries; astronomical databases and various aspects of the administration of astronomy libraries and services. Particular attention was paid to new developments, but the problems of astronomers and institutions in developing countries were also considered.
The IAU Strategic Plan "Astronomy for Development" - the next decade
NASA Astrophysics Data System (ADS)
Miley, George
We summarise the rationale for the IAU Strategic Plan "Astronomy for Development 2010 - 2020" and discuss lessons learned from its implementation that are relevant to the continuation of the IAU Astronomy for Development programme after 2020.
SOFA software support for IAU 2000
NASA Astrophysics Data System (ADS)
Wallace, P. T.
The IAU 2000 models for precession-nutation and Earth rotation offer a big step forward in accuracy. Not surprisingly, they are also larger than their predecessors (thousands of terms in some cases), but also they involve dealing with complications that previously were below practical limits on accuracy. These considerations make using standard software especially attractive, and the IAU SOFA collection provides implementations of the IAU 2000 algorithms that offer the full accuracy and yet are easy to use for everyday applications. A striking feature of the IAU 2000 models is that the ecliptic and equinox have been downgraded in status and no longer provide the zero-point in right ascension. The new origin is a point on the celestial equator close to its intersection with the ICRS prime meridian, but defined kinematically. The counterpart of Greenwich apparent sidereal time when using this new origin is the Earth Rotation Angle, which is linearly related to UT1. Though the new approach offers a number of advantages, stemming from the clean separation between Earth pole orientation and Earth rotation, it is sufficiently different from the existing equinox-based approach that many users will be reluctant or unable to make the switch. The SOFA routines cater for this by providing equal levels of support for both the classical equinox-based approach and for the new approach. The two options give results that agree to microarcsecond accuracy.
The IAU Strategic Plan and its Implementation
NASA Astrophysics Data System (ADS)
Miley, George
I shall review the content of the IAU Strategic Plan (SP) to use astronomy as a tool for stimulating development globally during the decade 2010 - 2020. Considerable progress has been made in its implementation since the Plan was ratified at the last General Assembly.
Colloquium: Nanoplasmas generated by intense radiation
NASA Astrophysics Data System (ADS)
Ostrikov, Kostya Ken; Beg, Farhat; Ng, Andrew
Solid, liquid, and gaseous states of matter can exist and acquire unique properties when reduced in size into a nanometer domain. This Colloquium explores the approaches to produce plasmas with nanometer dimensions and the arising physical phenomena and properties associated with this extreme, nonequilibrium state of matter. Analysis of the spatial confinement, coupling, ideality, and degeneracy criteria lead to the possibilities to produce transient nanoplasma states near, in, and from solids by using ultrafast photoexcitation. These states arise through the interplay of nonequilibrium, many-body Coulomb interactions, thermal, and nonthermal effects. Examples include photoexcited electron-hole plasmas in semiconductors, transient solid-to-plasma states including warm dense matter, nanoplasmas produced by interaction of nanoclusters and nanoparticles with intense radiation, nanoplasmas in high-energy ion tracks within solids, nanoplasmas in relativistic regime, and others. Physical phenomena arising due to the localization of high-energy densities to microscales and nanoscales and their potential applications are discussed.
Data Archiving: The Perspective of the IAU
NASA Astrophysics Data System (ADS)
Griffin, R. E.
Historically, the archiving of photographic observations has been predominantly a service on behalf of the astronomical community, both local and worldwide. In parallel, efforts to ensure the long-term preservation of that material have mostly come through the community at large via its official body, the International Astronomical Union. While the rôle of the IAU is largely passive, it is vital in providing a framework in which its international Working Groups can share, manage and achieve decisions and co-operations at levels which would be difficult to reach by individual action. To serve the purposes for which they have been archived, historic data need to be kept ticking over in a healthy condition. The IAU provides an excellent forum for the activities which those needs entail.
The IAU Office of Astronomy for Development
NASA Astrophysics Data System (ADS)
Govender, Kevin
The IAU Office of Astronomy for Development (OAD)†, established in March 2011 as part of the implementation of the IAU Strategic Plan, is currently located in South Africa and serves as a global coordinating centre for astronomy-for-development activities. In terms of structure the OAD is required to establish regional nodes (similar offices in different parts of the world which focus on a particular geographic or cultural region) and three task forces: (i) Astronomy for Universities and Research, (ii) Astronomy for Children and Schools, and (iii) Astronomy for the Public. This paper will describe the progress of the OAD towards the realisation of the vision `Astronomy for a better world'.
The IAU Office of Astronomy Development
NASA Astrophysics Data System (ADS)
Mauduit, Jean-Christophe; Govender, K.
The International Astronomical Union (IAU), the largest body of professional astronomers in the world, has set up the Office of Astronomy for Development (OAD) in partnership with the South African National Research Foundation (NRF). The OAD is located at the South African Astronomical Observatory (SAAO) in Cape Town. Its mission is to realise the IAU's Strategic Plan, which aims to use astronomy as a tool for development. It focuses on the following three main areas: "Universities and Research", "Children and Schools" and "Public Outreach". Eighteen projects worldwide have been funded for 2013 and are currently under way. More will be starting in 2014. The OAD is also setting up regional nodes and language expertise centres around the world. This presentation will describe the ongoing activities of the OAD and plans for the future.
The IAU Meteor Shower Nomenclature Rules
NASA Astrophysics Data System (ADS)
Jenniskens, Peter
The International Astronomical Union at its 2006 General Assembly in Prague has adopted a set of rules for meteor shower nomenclature, a working list with designated names (with IAU numbers and three-letter codes), and established a Task Group for Meteor Shower Nomenclature in Commission 22 (Meteors and Interplanetary Dust) to help define which meteor showers exist from well defined groups of meteoroids from a single parent body.
Colloquium: Topological band theory
NASA Astrophysics Data System (ADS)
Bansil, A.; Lin, Hsin; Das, Tanmoy
The first-principles band theory paradigm has been a key player not only in the process of discovering new classes of topologically interesting materials, but also for identifying salient characteristics of topological states, enabling direct and sharpened confrontation between theory and experiment. This review begins by discussing underpinnings of the topological band theory, which involve a layer of analysis and interpretation for assessing topological properties of band structures beyond the standard band theory construct. Methods for evaluating topological invariants are delineated, including crystals without inversion symmetry and interacting systems. The extent to which theoretically predicted properties and protections of topological states have been verified experimentally is discussed, including work on topological crystalline insulators, disorder and interaction driven topological insulators (TIs), topological superconductors, Weyl semimetal phases, and topological phase transitions. Successful strategies for new materials discovery process are outlined. A comprehensive survey of currently predicted 2D and 3D topological materials is provided. This includes binary, ternary, and quaternary compounds, transition metal and f -electron materials, Weyl and 3D Dirac semimetals, complex oxides, organometallics, skutterudites, and antiperovskites. Also included is the emerging area of 2D atomically thin films beyond graphene of various elements and their alloys, functional thin films, multilayer systems, and ultrathin films of 3D TIs, all of which hold exciting promise of wide-ranging applications. This Colloquium concludes by giving a perspective on research directions where further work will broadly benefit the topological materials field.
Chapter VIII: Rules and Guidelines for IAU Scientific Meetings
NASA Astrophysics Data System (ADS)
The program of IAU scientific meetings is one of the most important means by which the IAU pursues its goal of promoting astronomy through international collaboration. A large fraction of the Union's budget is devoted to the support of these IAU scientific meetings. The IAU Executive Committee (EC) places great emphasis on maintaining high scientific standards, coverage of a balanced spectrum of topics, and an appropriately broad and international flavour for the program of IAU meetings. In that respect, the ICSU rules on non-discrimination in the access of qualified scientists from all parts of the world to any IAU meeting apply. The ICSU rules on non-discrimination are described in the document "Freedom, Responsibility and Universality of Science", available on http://www.icsu.org/Gestion/img/ICSU_DOC_DOWNLOAD/2205_DD_FILE_Freedom_Responsibility_Universality_of_Science_booklet.pdf
Nineteenth NASTRAN (R) Users' Colloquium
NASA Technical Reports Server (NTRS)
The proceedings of the the Nineteenth NASTRAN Users' Colloquium held April 22 to 26, 1991 are presented. Topics covered include the application of finite elements in engineering, comparisons with other approaches, unique applications, pre- and postprocessing or auxiliary programs, and new methods of analysis with NASTRAN.
Fourteenth NASTRAN (R) Users' Colloquium
NASA Technical Reports Server (NTRS)
The proceedings of a colloquium are presented along with technical papers contributed during the conference. Reviewed are general applications of finite element methodology and the specific application of the NASA Structural Analysis System, NASTRAN, to a variety of static and dynamic sturctural problems.
Eighteenth NASTRAN (R) Users' Colloquium
NASA Technical Reports Server (NTRS)
This publication is the proceedings of the Eighteenth NASTRAN Users' Colloquium held in Portland, Oregon, April 23-27, 1990. It provides some comprehensive general papers on the application of finite elements in engineering, comparisons with other approaches, unique applications, pre- and post-processing or auxiliary programs, and new methods of analysis with NASTRAN.
Sixteenth NASTRAN (R) Users' Colloquium
NASA Technical Reports Server (NTRS)
These are the proceedings of the Sixteenth NASTRAN Users' Colloquium held in Arlington, Virginia from 25 to 29 April, 1988. Technical papers contributed by participants review general application of finite element methodology and the specific application of the NASA Structural Analysis System (NASTRAN) to a variety of static and dynamic structural problems.
The Second Colloquium on Petroleum Engineering Education
Willhite, G.P.; Forney, R.H.
This paper describes findings from the Second Colloquium on Petroleum engineering Education. The purpose of this colloquium was to provide a forum for petroleum engineering educators and representatives from industry and government to explore critical issues facing petroleum engineering education as we move into the 21st Century. It was expected that the colloquium would identify areas where changes are needed in petroleum engineering education, to best prepare students for careers in the oil and gas industry or other, related industries.
IAU Project and Research Activity in Nepal
NASA Astrophysics Data System (ADS)
Gautam, Suman
The second half of the twentieth century has witnessed a tremendous development in the field of astronomy and space exploration. The large telescope both on the land and in the orbit, using the whole range of the electromagnetic spectra from radio waves to gamma rays are extending their range of exploration, right to the edge of the observable universe, and making astounding discoveries in the process. Many large international telescope facilities and global plans are accessible to all astronomers throughout the world, providing an inexpensive entry to cutting- edge international research for developing countries.Nepal is a mountainous country it has a wide range of climatic and altitude variations which varies from an elevation of 200 meter to ≥ 4000 meter. The average temperature varies from ≥ 25 o C to ≤ 0 to 5oC. Because of these diverse weather and climatic variation there is the potential for the establishment of sophisticated observatory/ data centre and link with each other. So, the future possible opportunity of astronomy in Nepal will be discussed. Besides Education and Research activities conducted in Tribhuvan University, Nepal under the support of International Astronomical Union (IAU) will also be highlighted. The importance brought by those two workshops conducted on data simulation supported by IAU under TF1 will also be discussed which is believed to play a vital role for the promotion and development of astronomy and astrophysics in developing countries.
Sourcing and Communicating Cosmic Narratives -- A Role for the IAU?
NASA Astrophysics Data System (ADS)
Waller, William Howard
Communicating astronomy critically depends on crafting competent and engaging stories. IAU Commission 55 has an opportunity to take the lead in exploring and celebrating astronomical narratives. Possibilities include an online "Astro Tales" publication of astronomical stories by IAU members for the general public (that complements the trade-oriented CAP), "Profiles in Astronomy" that feature interviews with IAU members, forums featuring exceptional science communicators and their cosmic stories, writing competitions for students, and an awards program. Through some version of these endeavors, the IAU could become a major arbiter of astronomical information and outreach worldwide. In this session, Dr. Waller will use his online journal "The Galactic Inquirer" at http://galacticinquirer.net as an exemplar and encourage input from participants.
Algorithm for IAU north poles and rotation parameters
NASA Technical Reports Server (NTRS)
Lieske, J. H.
In 1970 the International Astronomical Union (IAU) defined any object's north pole to be that axis of rotation which lies north of the solar system's invariable plane. A competing definition in widespread use at some institutions followed the 'right hand rule' whereby the 'north' axis of rotation was generally said to be that of the rotational angular momentum. In the case of the latter definition, the planet Neptune and its satellite Triton would have their 'north' poles in opposite hemispheres because Triton's angular momentum vector is in the hemisphere opposite from that of Neptune's rotation angular momentum. The IAU resolutions have been somewhat controversial in some quarters ever since their adoption. A Working Group has periodically updated the recommended values of planet and satellite poles and rotation rates in accordance with the IAU definition of north and the IAU definition of prime meridian. Neither system is completely satisfactory in the perception of all scientists, and some confusion has been generated by publishing data in the two different systems. In this paper we review the IAU definitions of north and of the location of prime meridian and we present the algorithm which has been employed in determining the rotational parameters of the natural satellites. The IAU definition of the prime meridian contains some ambiguities which in practice have been 'specified' by the numerical values published by the IAU working group but which have not yet been explicitly documented. The purpose of this paper is to explicitly document the algorithm employed by the IAU working group in specifying satellite poles and rotation rates.
The IAU Early French Radio Astronomy Project
NASA Astrophysics Data System (ADS)
Orchiston, Wayne; Boischot, A.; Delannoy, J.; Kundu, M.; Lequeux, J.; Pick, M.; Steinberg, J.
In 2006 an ambitious project was launched under the auspices of the IAU Working Group on Historic Radio Astronomy to document important developments in French radio astronomy from 1901 through to the 1960s, in a series of papers published, in English, in the Journal of Astronomical History and Heritage. This successful project has now come to an end with the sixth and final paper in the series about to be published (and a new WG project, on the history of early Japanese radio astronomy, has just been launched). In this paper we discuss Nordmann's abortive attempt to detect solar radio emission in 1901, and the important roles played by staff from the École Normale Supérieure and the Institut d'Astrophysique in Paris during the 1940s through 60s in developing new radio astronomy instrumentation and pursuing a range of solar and non-solar research projects in Paris itself and at field stations established at Marcoussis, Nançay and the Haute Provence Observatory.
Northern Taurids in the IAU MDC Database
NASA Astrophysics Data System (ADS)
Kaňuchová, Z.; Svoreň, J.
The method of indices was used to study the northern branch of the autumn (night) part of the Taurid complex. The procedure based only on mathematical statistics was applied to select the Northern Taurid meteor records from the IAU Meteor Data Center Database. Because we wanted to study especially the structure of the inner part of the Northern Taurids, we were focused on the interval of the higher activity of the stream — from the end of the Perseids activity to the beginning of the Geminids activity. We did not take into account outlying parts of the complex, which is active, according to some authors, until January. 84 orbits of the Northern Taurids were selected. 63 of 84 Northern Taurids orbits (75%) were sorted into 11 associations found in the stream. One of the associations consisting of three orbits was identified as a previously unknown northern branch of τ Arietids shower. We also found an association with orbital characteristics equal to the characteristics of showers δ Psc N and χ Ori N. Meteors in these associations were observed up to three weeks earlier compared to currently cataloged data of the showers. The orientation of the mean orbit of a 5-member association of δ Psc N, different from the general trend, indicates that this stream may not be genetically related to other members of the Taurid complex.
Astronomy Thesaurus and IAU WG Libraries
NASA Astrophysics Data System (ADS)
Biemesderfer, C.
There has been interest lately in updated thesaurus data for astronomy. Both AIP and IOP independently initiated efforts to revise their comprehensive physics thesauri, and ADS and the IVOA have been working on similar projects. The impetus for all of this is semantic enrichment of the existing corpuses that these organizations hold. Earlier in 2012, AIP and IOP decided to combine forces on a physics thesaurus, and they engaged Access Innovations, a company with expertise in thesaurus constr uction, to help them. The team at ADS expressed interest in the project, and both publishers ag reed that they would release the astrophysics portion of the new combined thesaurus to the astronomical community. We are in the process of assigning its ownership to the AAS, although the thesaurus will be stewarded by staff affiliated with the CfA library, and the development will continue to be done under ADS guidance. All these combined efforts are being referred to as the Unified Astronomy Thesaurus (UAT). Previously, the IAU endorsed a thesaurus that was assembled in the early 1990s by Robyn and Robert Shobbrook at ANU. It was released in print, and was subsequently turned into a website. See the subsequent article for details about the UAT.
SOFA-an IAU service fit for the future
NASA Astrophysics Data System (ADS)
Hohenkerk, C.
Standards of Fundamental Astronomy (SOFA) is an International Astronomical Union (IAU) service that provides accessible and authoritative algorithms and procedures that implement standard models used in fundamental astronomy. This paper summaries the current status, noting the changes during 2009-2012, and discusses issues that may arise in the future.
Implementing the IAU 2000 Resolutions in The Astronomical Almanac
NASA Astrophysics Data System (ADS)
Bangert, J. A.; Kaplan, G. H.; Hilton, J. L.; Hohenkerk, C. Y.; Bell, S. A.
The Astronomical Almanac (AsA) must satisfy the needs of a variety of users around the world, who represent a wide range of interests and sophistication levels. The book, prepared jointly by the US and UK nautical almanac offices, is based to the greatest extent possible on IAU-endorsed and other internationally recognized standards. Many users expect that the general content and format of the AsA will remain the same from year to year. Thus, changes to the AsA are made as infrequently as possible, and only after careful deliberation. The IAU resolutions on reference systems and Earth rotation adopted in 2000 represent a significant change in approach for both subject areas. To implement these resolutions in the content of the AsA, both the reference data and algorithms used must be changed, and some new tabulations added. Data in the ``IAU 2000 paradigm" will not replace data provided in the traditional or ``classical" paradigm until the needs of the user community dictate that such a change is warranted. General criteria that determine when changes are introduced into the AsA will be reviewed. Specific changes to the AsA needed to implement the IAU 2000 resolutions will be described, and several remaining issues will be discussed. These changes will be introduced beginning in the AsA for 2006, currently in preparation.
The Updated IAU MDC Catalogue of Photographic Meteor Orbits
NASA Technical Reports Server (NTRS)
Porubcan, V.; Svoren, J.; Neslusan, L.; Schunova, E.
The database of photographic meteor orbits of the IAU Meteor Data Center at the Astronomical Institute SAS has gradually been updated. To the 2003 version of 4581 photographic orbits compiled from 17 different stations and obtained in the period 1936-1996, additional new 211 orbits compiled from 7 sources have been added. Thus, the updated version of the catalogue contains 4792 photographic orbits (equinox J2000.0) available either in two separate orbital and geophysical data files or a file with the merged data. All the updated files with relevant documentation are available at the web of the IAU Meteor Data Center. Keywords astronomical databases photographic meteor orbits 1 Introduction Meteoroid orbits are a basic tool for investigation of distribution and spatial structure of the meteoroid population in the close surroundings of the Earth s orbit. However, information about them is usually widely scattered in literature and often in publications with limited circulation. Therefore, the IAU Comm. 22 during the 1976 IAU General Assembly proposed to establish a meteor data center for collection of meteor orbits recorded by photographic and radio techniques. The decision was confirmed by the next IAU GA in 1982 and the data center was established (Lindblad, 1987). The purpose of the data center was to acquire, format, check and disseminate information on precise meteoroid orbits obtained by multi-station techniques and the database gradually extended as documented in previous reports on the activity of the Meteor Data Center by Lindblad (1987, 1995, 1999 and 2001) or Lindblad and Steel (1993). Up to present, the database consists of 4581 photographic meteor orbits (Lindblad et al., 2005), 63.330 radar determined orbit: Harvard Meteor Project (1961-1965, 1968-1969), Adelaide (1960-1961, 1968-1969), Kharkov (1975), Obninsk (1967-1968), Mogadish (1969-1970) and 1425 video-recordings (Lindblad, 1999) to which additional 817 video meteors orbits published by Koten el
Dynamics of quiescent prominences; Proceedings of the 117th Colloquium of IAU, Hvar, Yugoslavia, Sept. 25-29, 1989
NASA Technical Reports Server (NTRS)
Ruzdjak, Vladimir (Editor); Tandberg-Hanssen, Einar (Editor)
Topics discussed include formation of a filament around a magnetic region, evolution of fine structures in a filament, the spatial distribution of prominence threads, high resolution analysis of quiescent prominences at NSO/Sacramento Peak Observatory, small-scale Doppler velocities in a quiescent prominence, Doppler velocity oscillations in quiescent prominences, oscillatory relaxation of an eruptive prominence, and matter flow velocities in an active region emission loop observed in H-alpha. Attention is also given to an automated procedure for measurement of prominence transverse velocities, the nonlinear evolution of magnetized filaments, thermal equilibrium of coronal loops and prominence formation, thermal instability in planar coronal strucutres, radiative transfer in cylindrical prominence threads, numerical simulation of a catastrophe model for prominence eruptions, and the law of evolution and destruction of solar prominences.
Proceedings of the Higher Education Colloquium.
ERIC Educational Resources Information Center
The Higher Education Colloquium is composed of individuals who have made significant contributions to American higher education as researchers, college or university administrators, foundation executives, or in other roles. These proceedings include the following: recognition of the efforts and excellence of Ruth E. Eckert; "New Tasks for New…
Precession-nutation procedures consistent with IAU 2006 resolutions
NASA Astrophysics Data System (ADS)
Wallace, P. T.; Capitaine, N.
Context: .The 2006 IAU General Assembly has adopted the P03 model of Capitaine et al. (2003a) recommended by the WG on precession and the ecliptic (Hilton et al. 2006) to replace the IAU 2000 model, which comprised the Lieske et al. (1977) model with adjusted rates. Practical implementations of this new "IAU 2006" model are therefore required, involving choices of procedures and algorithms. Aims: .The purpose of this paper is to recommend IAU 2006 based precession-nutation computing procedures, suitable for different classes of application and achieving high standards of consistency. Methods: .We discuss IAU 2006 based procedures and algorithms for generating the rotation matrices that transform celestial to terrestrial coordinates, taking into account frame bias (B), P03 precession (P), P03-adjusted IAU 2000A nutation (N) and Earth rotation. The NPB portion can refer either to the equinox or to the celestial intermediate origin (CIO), requiring either the Greenwich sidereal time (GST) or the Earth rotation angle (ERA) as the measure of Earth rotation. Where GST is used, it is derived from ERA and the equation of the origins (EO) rather than through an explicit formula as in the past, and the EO itself is derived from the CIO locator. Results: .We provide precession-nutation procedures for two different classes of full-accuracy application, namely (i) the construction of algorithm collections such as the Standards Of Fundamental Astronomy (SOFA) library and (ii) IERS Conventions, and in addition some concise procedures for applications where the highest accuracy is not a requirement. The appendix contains a fully worked numerical example, to aid implementors and to illustrate the consistency of the two full-accuracy procedures which, for the test date, agree to better than 1 μas. Conclusions: .The paper recommends, for case (i), procedures based on angles to represent the PB and N components and, for case (ii), procedures based on series for the CIP X,Y. The two
The IAU's East Asian Regional Office of Astronomy for Development
NASA Astrophysics Data System (ADS)
de Grijs, Richard
At the 2012 General Assembly of the International Astronomical Union (IAU), the Office of Astronomy for Development (OAD) programme announced a number of exciting new partnerships to assist with the IAU's decadal strategic plan (2010-2020). These landmark decisions included establishing a new coordinating centre that aims at using astronomy as a tool for development in East Asia. The agreement covers two important functions. One is known as a Regional Node, which entails the coordination of astronomy-for-development activities in countries within the general geographical region of East Asia (in first instance China, Mongolia and the DPRK, but without placing firm geographical limits on the region). The other is known as a Language Expertise Centre which will deal with all aspects relating to (mainly) the Chinese language and culture. The impact of the latter may obviously spread well beyond the geographical region to other parts of the world.
The IAU 2000 Recommendations on Reference Systems and their Application
NASA Astrophysics Data System (ADS)
Capitaine, N.; McCarthy, D. D.
Resolutions adopted by the International Astronomical Union (IAU) in 2000 recommend significant improvements in the definition of the International Celestial Reference System and the procedures to be used in its realization. These recommendations correspond with the unprecedented observational accuracy that is now achievable in accessing the reference system, and deal with relativistic considerations, an improved precession-nutation formulation, and more rigorous definitions of the pole and equatorial origin of the reference system. The International Earth Rotation Service (IERS) has implemented these recommendations and maintains the necessary software and data files to allow the astronomical and geodetic communities to use them. It also continues to provide the data necessary to implement the previous definitions. These recommendations are not only addressed to the specialized astronomical community that deals with the realization or maintenance of reference systems, time scales, celestial mechanics and high accuracy astrometry. They have consequences for the whole astronomical community as they relate to the IAU precession-nutation model, the definition of Universal Time and its relationship to sidereal time and the abandonment of the intermediary reference to the ecliptic and equinox. At its 2003 General Assembly the IAU established working groups to finalize the implementation of the 2000 resolutions, namely (1) to standardize the associated new nomenclature and (2) to formulate a dynamical expression for precession consistent with the IAU 2000 precession-nutation formulation. This talk explains the reasons for these resolutions, describes their consequences for astronomers and provides the current status of their implementation. It also reports on the latest international discussions on nomenclature and educational efforts.
The I.A.U. meteor shower nomenclature rules
NASA Astrophysics Data System (ADS)
Jenniskens, Peter
The International Astronomical Union at its 2006 General Assembly in Prague has adopted a set of rules for meteor shower nomenclature, a working list with designated names (with IAU numbers and three-letter codes), and established a Task Group for Meteor Shower Nomenclature in Commission 22 (Meteors and Interplanetary Dust) to help define which meteor showers exist from well defined groups of meteoroids from a single parent body.
Expressions to implement the IAU 2000 definition of UT1
NASA Astrophysics Data System (ADS)
Capitaine, N.; Wallace, P. T.; McCarthy, D. D.
This paper provides expressions to be used to implement the new definition of UT1 corresponding to the IAU 2000 resolutions either in the new (CEO-based) or classical (equinox-based) transformations between the International Terrestrial Reference System (ITRS) and the Geocentric Celestial Reference System (GCRS). The new expression for Greenwich Sidereal Time (GST) has to be in agreement at the microarcsecond level, for one century, with the IAU 2000 expressions for the Earth Rotation Angle (ERA) and for the quantity s positioning the Celestial Ephemeris Origin (CEO) on the equator of the CIP. The computations of the new expressions using the IAU 2000 precession-nutation model are performed in such a manner as to ensure that there is no discontinuity in UT1 on 1 January 2003 and that there is equivalence of the classical and new transformations between the ITRS and GCRS relative to the rotation about the axis of the CIP when these expressions are used. The equinox offset that is considered in the computations refers to the dynamical mean equinox of J2000.0. The resulting expressions have been included in the IERS Conventions 2000.
1997 Atmospheric Chemistry Colloquium for Emerging Senior Scientists
Paul H. Wine
DOE's Atmospheric Chemistry Program is providing partial funding for the Atmospheric Chemistry Colloquium for Emerging Senior Scientists (ACCESS) and FY 1997 Gordon Research Conference in Atmospheric Chemistry
10 years of the IAU Efforts for Capitalizing the Ground-Based Astrometry
NASA Astrophysics Data System (ADS)
Stavinschi, Magda; Thuillot, William
In 2000 a new IAU working group was founded (IAU GA, Manchester): Future Development of Ground-Based Astrometry (FDGBA). It was revised in 2003 during the IAU GA in Sydney. A new one replaced it in 2006 (IAU GA, Prague): Astrometry by Small Ground-Based Telescopes (ASGBT). It was renewed for other three years during the IAU GA in Rio de Janeiro. The main aim of the working groups followed the Newsletter No. 1 of the IAU Commission 8, which says: The post-Hipparcos era has brought an element of uncertainty as to the goals and future programs for all of ground-based astrometry The purpose of the WGs was "to update and maintain information on astrometric programmes and activities carried out by small telescopes, to diffuse news through these pages and e-mails, to facilitate the collaborations and to help for the coordination of the activities, when possible, in astrometry from ground-based telescopes".
IAU Working Group for Numerical Standards of Fundamental Astronomy (NSFA): Past Efforts and Future Endeavors
NASA Astrophysics Data System (ADS)
Luzum, Brian; Capitaine, Nicole; Fienga, Agnès; Folkner, William M.; Fukushima, Toshio; Heinkelmann, Robert; Hilton, James L.; Hohenkerk, Catherine; Petit, Gérard; Pitjeva, Elena; Soffel, Michael; Wallace, Patrick
In 2006, the International Astronomical Union (IAU) General Assembly (GA) established the Working Group (WG) for Numerical Standards of Fundamental Astronomy (NSFA). The NSFA WG Current Best Estimates (CBEs) were adopted at the 2009 IAU GA in Resolution B2 as the IAU (2009) System of Astronomical Constants. The IAU 2012 Resolution on the re-definition of the au was proposed by the NSFA WG. Since then, the WG has concentrated on establishing the process for maintaining the CBEs in an effort to provide a service for the IAU. The NSFA web presence documents both the IAU (2009) System of Astronomical Constants and the CBEs. All old pages of the CBEs are archived in order to document history of the CBEs. The CBE policy documents the procedures established for proposal, discussion, and voting for the adoption of new CBEs. The talk reviews the efforts of the WG and provides insight into future efforts.
Galileo's Medicean Moons (IAU S269)
NASA Astrophysics Data System (ADS)
Barbieri, Cesare; Chakrabarti, Supriya; Coradini, Marcello; Lazzarin, Monica
Preface; 1. Galileo's telescopic observations: the marvel and meaning of discovery George V. Coyne, S. J.; 2. Popular perceptions of Galileo Dava Sobel; 3. The slow growth of humility Tobias Owen and Scott Bolton; 4. A new physics to support the Copernican system. Gleanings from Galileo's works Giulio Peruzzi; 5. The telescope in the making, the Galileo first telescopic observations Alberto Righini; 6. The appearance of the Medicean Moons in 17th century charts and books. How long did it take? Michael Mendillo; 7. Navigation, world mapping and astrometry with Galileo's moons Kaare Aksnes; 8. Modern exploration of Galileo's new worlds Torrence V. Johnson; 9. Medicean Moons sailing through plasma seas: challenges in establishing magnetic properties Margaret G. Kivelson, Xianzhe Jia and Krishan K. Khurana; 10. Aurora on Jupiter: a magnetic connection with the Sun and the Medicean Moons Supriya Chakrabarti and Marina Galand; 11. Io's escaping atmosphere: continuing the legacy of surprise Nicholas M. Schneider; 12. The Jovian Rings Wing-Huen Ip; 13. The Juno mission Scott J. Bolton and the Juno Science Team; 14. Seeking Europa's ocean Robert T. Pappalardo; 15. Europa lander mission: a challenge to find traces of alien life Lev Zelenyi, Oleg Korablev, Elena Vorobyova, Maxim Martynov, Efraim L. Akim and Alexander Zakahrov; 16. Atmospheric moons Galileo would have loved Sushil K. Atreya; 17. The study of Mercury Louise M. Prockter and Peter D. Bedini; 18. Jupiter and the other giants: a comparative study Thérèse Encrenaz; 19. Spectroscopic and spectrometric differentiation between abiotic and biogenic material on icy worlds Kevin P. Hand, Chris McKay and Carl Pilcher; 20. Other worlds, other civilizations? Guy Consolmagno, S. J.; 21. Concluding remarks Roger M. Bonnet; Posters; Author index; Object index.
IAU Office of Astronomy for Development: Task Force Children and School Education
NASA Astrophysics Data System (ADS)
Russo, Pedro; Gomez, Edward
The main mission of the IAU OAD Task Force on Children and School Education is to support the implementation of the pre-tertiary education part of the IAU Strategic Plan `Astronomy for Development'. In this presentation we will give an overview of the role and programme of the task force as well as a general discussion about the past, present and future IAU education activities and programmes.
Catherine Cesarsky - President Elect of the International Astronomical Union (IAU)
NASA Astrophysics Data System (ADS)
The General Assembly of the International Astronomical Union (IAU), meeting in Sydney (Australia), has appointed the ESO Director General, Dr. Catherine Cesarsky, as President Elect for a three-year period (2003-2006). The IAU is the world's foremost organisation for astronomy, uniting almost 9000 professional scientists on all continents. The IAU General Assembly also elected Prof. Ron Ekers (Australia) as President (2003 - 2006). Dr. Cesarsky will then become President of the IAU in 2006, when the General Assembly next meets in Prague (The Czech Republic). Dr. Cesarsky is the first woman scientist to receive this high distinction. "The election of Catherine Cesarsky as President-Elect of the IAU is an important recognition for a scientist who has made impressive contributions to various areas of modern astrophysics, from cosmic rays to the interstellar medium and cosmology" , commented the outgoing IAU President, Prof. Franco Pacini. "It is also an honour and an important accolade for the European astronomical community in general and ESO in particular." Dr. Cesarsky, who assumed the function as ESO Director General in 1999, was born in France. She received a degree in Physical Sciences at the University of Buenos Aires and graduated with a PhD in Astronomy in 1971 from Harvard University (Cambridge, Mass., USA). Afterwards she worked at the California Institute of Technology (CALTECH). In 1974, she became a staff member of the Service d'Astrophysique (SAp), Direction des Sciences de la Matière (DSM), Commissariat à l'Energie Atomique (CEA) (France). As Director of DSM (1994 - 1999), she was leading about 3000 scientists, engineers and technicians active within a broad spectrum of basic research programmes in physics, chemistry, astrophysics and earth sciences. Dr. Cesarsky is known for her successful research activities in several central areas of modern astrophysics. She first worked on the theory of cosmic ray propagation and acceleration, and galactic gamma
The Russian Astronomical Yearbooks and IAU 2000 Resolutions
NASA Astrophysics Data System (ADS)
Glebova, N. I.; Lukashova, M. V.; Sveshnikov, M. L.
According to IAU 2000 resolutions, a reform of IAA RAS publications has been carried out during 2003-2006. In "The Astronomical Yearbook for 2007" the ephemerides of the Sun, the Moon and major planets are based on EPM 2004 theory developed in IAA RAS with accuracy adequate to DE405/LE405. Apparent places of stars are given in FK6/HIPPARCOS system referred to ICRS, and are calculated taking into account the new IAU 2000 model of nutation and the new IERS 2003 precession model which is practically close to P03 model. The sidereal time was determined by the Earth rotation angle. Coordinates of pole X, Y, CIO locator s and the equation of the origins are also presented. Matrixes of conversions from ICRS to the true equator and the equinox of date, as well as to the celestial intermediate origin and the true equator date are given. Navigating ephemerides are issued as "The Nautical Astronomical Yearbook" and "The Nautical Astronomical Almanac" biennial on the basis of DE405/LE405, new precession-nutation model, FK6/HIPPARCOS catalogues and the classical concept of the equinox. Nevertheless, the implementation of the new CIO concept in navigating ephemerides tables cannot be planned yet. At IAA RAS, the electronic versions of astronomical yearbooks have been developed allowing to calculate topocentric ephemerides. All the calculations are made with a specialized ERA programming system created in IAA RAS using the problem-oriented programming language for the solution of problems of ephemeris and dynamic astronomy.
The Sun as a variable star: Solar and stellar irradiance variations; Colloquium of the International Astronomical Union, 143rd, Boulder, CO, Jun. 20-25, 1993
NASA Technical Reports Server (NTRS)
Pap, Judit M. (Editor); Froehlich, Claus (Editor); Hudson, Hugh S. (Editor); Tobiska, W. Kent (Editor)
Variations in solar and stellar irradiances have long been of interest. An International Astronomical Union (IAU) colloquium reviewed such relevant subjects as observations, theoretical interpretations, and empirical and physical models, with a special emphasis on climatic impact of solar irradiance variability. Specific topics discussed included: (1) General Reviews on Observations of Solar and Stellar Irradiance Variability; (2) Observational Programs for Solar and Stellar Irradiance Variability; (3) Variability of Solar and Stellar Irradiance Related to the Network, Active Regions (Sunspots and Plages), and Large-Scale Magnetic Structures; (4) Empirical Models of Solar Total and Spectral Irradiance Variability; (5) Solar and Stellar Oscillations, Irradiance Variations and their Interpretations; and (6) The Response of the Earth's Atmosphere to Solar Irradiance Variations and Sun-Climate Connections.
Evolutionary games on multilayer networks: a colloquium
NASA Astrophysics Data System (ADS)
Wang, Zhen; Wang, Lin; Szolnoki, Attila; Perc, Matjaž
Networks form the backbone of many complex systems, ranging from the Internet to human societies. Accordingly, not only is the range of our interactions limited and thus best described and modeled by networks, it is also a fact that the networks that are an integral part of such models are often interdependent or even interconnected. Networks of networks or multilayer networks are therefore a more apt description of social systems. This colloquium is devoted to evolutionary games on multilayer networks, and in particular to the evolution of cooperation as one of the main pillars of modern human societies. We first give an overview of the most significant conceptual differences between single-layer and multilayer networks, and we provide basic definitions and a classification of the most commonly used terms. Subsequently, we review fascinating and counterintuitive evolutionary outcomes that emerge due to different types of interdependencies between otherwise independent populations. The focus is on coupling through the utilities of players, through the flow of information, as well as through the popularity of different strategies on different network layers. The colloquium highlights the importance of pattern formation and collective behavior for the promotion of cooperation under adverse conditions, as well as the synergies between network science and evolutionary game theory.
History of Astronomy Under the Auspices of the IAU
NASA Astrophysics Data System (ADS)
Kochhar, Rajesh; Sun, Xiaochun; Ruggles, Clive; Avilés, Juan Antonio Belmonte; Corbin, Brenda; Milone, Eugene; Norris, Raymond; Oigatto, Luisa; Sōma, Mitsuru
International Astronomical Union was formed after the First World War although it became truly international only after the Second World War. Its Commission 41 on History of Astronomy (C41) was set up in 1948 and in a few years established itself as an active and influential unit. It has the distinction of being a joint Commission, the other partner being International Union of History and Philosophy of Science and Technology (IUHPS). Since IAU is an internationally respected body of professional astronomers, its support for history of astronomy enhances the credibility of the discipline in the eyes of scientists as well as science establishments of individual countries. C41 is committed to advancing objective and rigorous world history of astronomy taking into account all its aspects.
Communication strategies and volunteer management for the IAU-OAD
NASA Astrophysics Data System (ADS)
Sankatsing Nava, Tibisay
The IAU Office of Astronomy for Development will be developing a new communication strategy to promote its projects in a way that is relevant to stakeholders and the general public. Ideas include a magazine featuring best practices within the field of astronomy for development and setting up a workflow of communication that integrates the different outputs of the office and effectively uses the information collection tools developed by OAD team members.To accomplish these tasks the OAD will also develop a community management strategy with existing tools to effectively harness the skills of OAD volunteers for communication purposes. This talk will discuss the new communication strategy of the OAD as well the expanded community management plans.
Confirmation of the chi Cygnids (CCY, IAU#757)
NASA Astrophysics Data System (ADS)
Koukal, J.; Srba, J.; Tóth, J.
In this paper we present independent confirmation of the existence of the chi Cygnid (CCY, IAU#757) meteor shower. The chi Cygnids were discovered by Peter Jenniskens within the frame of CAMS project (Cameras for Allsky Meteor Surveillance). Thanks to the cooperation between European viDeo MeteOr Network (EDMONd), International Meteor Organization Video Meteor Network (IMO VMN) and the BRAzilian Meteor Observation Network (BRAMON) the current version of the EDMOND database (v5.02) contains 189 323 multi-station meteor orbits. This large data sample allowed confirmation of the increased activity from the chi Cygnid swarm during the night of 2015 September 14/15, and also made it possible to map the activity of this newly discovered swarm during the years 2001-2014.
El Sistema de Referencia Celeste convencional de la IAU
NASA Astrophysics Data System (ADS)
Arias, E. F.
La Unión Astronómica Internacional (IAU) recomendó la adopción de un nuevo sistema de referencia celeste baricéntrico cuyo plano fundamental y origen de ascensiones rectas estén próximos, respectivamente, al ecuador y equinoccio dinámicos J2000.0. El nuevo sistema de referencia estará materializado por las posiciones J2000.0 de radiofuentes extragalácticas determinadas con la técnica de interferometría de larga línea de base (VLBI). El Working Group on Reference Frames de la IAU (WGRF) decidió adoptar (Grasse, 1995) al sistema de referencia celeste extragaláctico del Servicio Internacional de la Rotación Terrestre (IERS) como futuro sistema de referencia celeste convencional bajo el nombre International Celestial Reference System (ICRS) y encomendó su mantenimiento futuro al IERS. El marco de referencia que materializará al ICRS contiene posiciones precisas J2000.0 de más de 600 radiofuentes extragalácticas. Las coordenadas fueron ajustadas en una única solución VLBI en la cual se incluyeron todas las observaciones realizadas hasta octubre de 1995 con la técnica de adquisición de datos VLBI Mark III. Para minimizar los errores sistemáticos que pueden afectar la calidad del marco de referencia se introdujeron mejoras sustanciales en la modelización y en la selección de datos. Un subconjunto de objetos del marco de referencia se utilizó para referir las posiciones estelares determinadas con el satélite astrométrico Hipparcos al ICRS.
Conference Report: The Sino-American Colloquium on Moral Cognition.
ERIC Educational Resources Information Center
Gielen, Uwe
Offers a report on a January 1987 colloquium on moral cognition in Chinese culture. Calls for creative teamwork on longitudinal interviews to gain a more exact picture of moral development structures in non-western cultures such as Taiwan. (BSR)
Supporting Papers for A Colloquium on the Vietnamese Language.
ERIC Educational Resources Information Center
Nguyen Hy Quang; Duong Thanh Binh
These papers were written as supporting documents for a colloquium on the Vietnamese language. The first catalogues and analyzes Vietnamese vowels, diphthongs, consonants and tones. The second analyzes some facets of Vietnamese syntax. (CHK)
The impact of the New IAU Resolutions on ICRF Definition and Realization
NASA Astrophysics Data System (ADS)
Capitaine, N.
Following the adoption of the International Celestial Reference System and Frame (ICRS and ICRF) by the IAU in 1997, several resolutions on reference systems have been passed by the IAU in 2000 and 2006 and endorsed by the IUGG in 2003 and 2007, respectively. These resolutions concern especially the transformation between the International Terrestrial Reference System (ITRS) and the Geocentric Celestial Reference system (GCRS) that is essential for realizing the ICRS from directions of extragalactic radio sources observed from the Earth by VLBI. First, the IAU 2000 resolutions have refined the concepts and definition of the astronomical reference systems and parameters for Earth's rotation, and adopted the IAU 2000 precession-nutation. Then, the IAU 2006 resolutions have adopted a new precession model that is consistent with dynamical theories and have addressed definition, terminology or orientation issues relative to reference systems and time scales that needed to be specified after the adoption of the IAU 2000 resolutions. These in particular provide a refined definition of the pole and the origin on the equator as well as a rigorous definition of sidereal rotation of the Earth. These also allow an accurate realization of the celestial intermediate system that replaces the classical celestial system based on the true equator and equinox of date. There was an additional IUGG 2007 resolution for the terrestrial reference system. Finally, the IAU 2009 resolutions have adopted a new system of astronomical constants - including conventional values of the IAU 2000/2006 resolutions - and adopted the Second Realization, ICRF2, of the International Celestial Reference Frame. This paper recalls the main aspects of these recent IAU resolutions as well as their consequences on the concepts, definitions, nomenclature and models that are suitable for modern realizations of reference systems. The impact of these resolutions on the definition and realization of the
IAU Resolution 2009 B5 - Commission 50 Draft Action Plan - Presentation and Discussion
NASA Astrophysics Data System (ADS)
Green, R. F.
IAU Resolution 2009 B5 calls on IAU members to protect the public's right to an unpolluted night sky as well as the astronomical quality of the sky around major research observatories. The multi-pronged approach of Commission 50 includes working with the lighting industry for appropriate products from the solid state revolution, arming astronomers with training and materials for presentation, selective endorsement of key protection issues, cooperation with several other IAU commissions for education and outreach, and provision of clear quantitative priorities for outdoor lighting standards.
Modern temporal network theory: a colloquium
NASA Astrophysics Data System (ADS)
Holme, Petter
The power of any kind of network approach lies in the ability to simplify a complex system so that one can better understand its function as a whole. Sometimes it is beneficial, however, to include more information than in a simple graph of only nodes and links. Adding information about times of interactions can make predictions and mechanistic understanding more accurate. The drawback, however, is that there are not so many methods available, partly because temporal networks is a relatively young field, partly because it is more difficult to develop such methods compared to for static networks. In this colloquium, we review the methods to analyze and model temporal networks and processes taking place on them, focusing mainly on the last three years. This includes the spreading of infectious disease, opinions, rumors, in social networks; information packets in computer networks; various types of signaling in biology, and more. We also discuss future directions.
Colloquium: Hierarchy of scales in language dynamics
NASA Astrophysics Data System (ADS)
Blythe, Richard A.
Methods and insights from statistical physics are finding an increasing variety of applications where one seeks to understand the emergent properties of a complex interacting system. One such area concerns the dynamics of language at a variety of levels of description, from the behaviour of individual agents learning simple artificial languages from each other, up to changes in the structure of languages shared by large groups of speakers over historical timescales. In this Colloquium, we survey a hierarchy of scales at which language and linguistic behaviour can be described, along with the main progress in understanding that has been made at each of them - much of which has come from the statistical physics community. We argue that future developments may arise by linking the different levels of the hierarchy together in a more coherent fashion, in particular where this allows more effective use of rich empirical data sets.
SPICE as an IAU Recommendation for Planetary Ephemerides
NASA Astrophysics Data System (ADS)
Acton, Charles; Bachman, Nathaniel; Folkner, William M.; Hilton, James
In 2010 the IAU Commission 4 Working Group (WG) on Standardizing Access to Ephemerides and File Format Specification was formed to define a portable standard for planetary ephemeris files. The standard would have to work for all three sources of ephemerides-NASA/JPL, Institut de mécanique céleste de calcul des éphémérides (IMCCE), and Institute of Applied Astronomy (IAA). The WG decided to base its standard on the existing "SPICE"* Spacecraft/Planet kernel (SPK) format.The SPK format was created for use with the "SPICE" information system, used by many scientists and engineers worldwide to compute the geometry needed to plan and analyze data from robotic missions. SPICE is comprised of both data files and associated software, all freely available. SPICE data files, usually referred to as "kernels," provide ephemerides and size, shape and orientation of solar system bodies; spacecraft trajectory and orientation; reference frame specifications and implementations; instrument field-of-view geometry; and time system conversion data.Standard SPICE ephemeris files use the TDB time system-the WG requested SPICE be extended to accommodate ephemerides based on the TCB time system. Extensions were also needed to accommodate the IAA ephemeris representation as well as the integrated difference between coordinate time and proper time in the form of TT-TDB and TCG-TCB.Software to read the SPK kernels defined to accommodate planetary ephemerides is available in the SPICE toolkit, and also in stand-alone kernel readers available from IMCEE and IAA.SPK is also used within the SPICE community for natural satellites, asteroids, and comets. Future IAU discussions might lead to an expansion of the work done for planets to provide more general standards for these bodies.Portions of the research described in this publication was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration
Northern Taurids in the IAU Meteor Data Center Database
NASA Astrophysics Data System (ADS)
Svoren, Jan; Kanuchova, Zuzana; Husarik, Marek
The method of indices was used to study the northern branch of the autumn (night) part of the Taurid complex. The procedure is based on mathematical statistics only and was applied to select the Northern Taurid meteor records from the IAU Meteor Data Center Database. Because we wanted to study especially the fine structure of the inner part of the Northern Taurids, we were focused on the interval of the higher activity of the stream - from the end of the activity of the Perseids until the beginning of the Geminids activity. The outlying parts of the complex, active until January according to some authors, were not taken into account. In total, 84 Northern Taurid orbits were selected. Of these 84 orbits, 63 (75%) were sorted into 11 associations found in the stream. One of the associations consisted of three orbits and was identified as a previously unknown northern branch of the Tau-Arietids. We also found an association with orbital characteristics equal to the characteristics of the Delta-Piscids North and the Chi-Orionids North. The meteors in these associations were observed up to three weeks earlier compared to the currently cataloged data of the showers. The orientation of the mean orbit of a 5-member association with the Delta-Piscids North was different from the general trend, indicating that this stream may not be genetically related to other members of the Taurid complex.
Industrial ecology: reflections on a colloquium.
Ausubel, J H
Industrial ecology is the network of all industrial processes as they may interact with each other and live off each other, not only in the economic sense, but also in the sense of direct use of each other's material and energy wastes and products. This paper, which reflects upon the papers and discussions at the National Academy of Sciences Colloquium on Industrial Ecology on May 20-21, 1991, is structured around 10 questions. Do sociotechnical systems have long-range environmental goals? How is the concept of industrial ecology useful and timely? What are environmental technologies? Is there a systematic way to choose among alternatives for improving the ecology of technologies? What are ways to measure performance with respect to industrial ecology? What are the sources and rates of innovation in environmental technologies? How is the market economy performing with respect to industrial ecology? What will be the effect of the ecological modernization of the developed nations of the North on the developing countries of the South? How can creative interaction on environmental issues be fostered among diverse social groups? How must research and education change? PMID:11607273
Colloquium: Annual modulation of dark matter
NASA Astrophysics Data System (ADS)
Freese, Katherine; Lisanti, Mariangela; Savage, Christopher
Direct detection experiments, which are designed to detect the scattering of dark matter off nuclei in detectors, are a critical component in the search for the Universe's missing matter. This Colloquium begins with a review of the physics of direct detection of dark matter, discussing the roles of both the particle physics and astrophysics in the expected signals. The count rate in these experiments should experience an annual modulation due to the relative motion of the Earth around the Sun. This modulation, not present for most known background sources, is critical for solidifying the origin of a potential signal as dark matter. The focus is on the physics of annual modulation, discussing the practical formulas needed to interpret a modulating signal. The dependence of the modulation spectrum on the particle and astrophysics models for the dark matter is illustrated. For standard assumptions, the count rate has a cosine dependence with time, with a maximum in June and a minimum in December. Well-motivated generalizations of these models, however, can affect both the phase and amplitude of the modulation. Shown is how a measurement of an annually modulating signal could teach us about the presence of substructure in the galactic halo or about the interactions between dark and baryonic matter. Although primarily a theoretical review, the current experimental situation for annual modulation and future experimental directions is briefly discussed.
Summaries of SpS17 Discussions IAU GA 2012 Special Session on Light Pollution
NASA Astrophysics Data System (ADS)
Walker, Constance E.; Parks, Bob; McKenna, Dan; Sefako, Ramotholo; Smith, Malcolm; Galadí-Enríquez, David
To address light pollution issues, IAU Commissions 41, 46, 50, and 55 are involved in getting the word out to the public and IAU members via cultural, educational, technical; however, efforts can always improve and evolve. To carry out a successful light pollution abatement program supported by the IAU, it takes a diversity of groups, professions, and disciplines with their collective knowledge and experience. In manifesting dark skies awareness effectively, we are stronger together than we are alone; therefore, combining efforts of Commissions 41, 46, 50 and 55 with organizations like the International Dark-Sky Association, Astronomers Without Borders, The World at Night and partnering with events like Earth Hour or GLOBE at Night is a good step forward.
MayDay Colloquium 24: The Aims of Music Education
ERIC Educational Resources Information Center
Elliott, David J.
On June 20, 2012, Professor John Kratus welcomed the MayDay Group to Michigan State University for "Colloquium 24: The Aims of Music Education". On behalf of all members of the Mayday Group, the author wishes to extend his deepest gratitude to Professor Kratus and his colleagues at Michigan State for their extremely gracious and…
Colloquium on Large Scale Improvement: Implications for AISI
ERIC Educational Resources Information Center
McEwen, Nelly, Ed.
The Alberta Initiative for School Improvement (AISI) is a province-wide partnership program whose goal is to improve student learning and performance by fostering initiatives that reflect the unique needs and circumstances of each school authority. It is currently ending its third cycle and ninth year of implementation. "The Colloquium on Large…
Changing Currents in Second Language Writing Research: A Colloquium.
ERIC Educational Resources Information Center
Matsuda, Paul Kei; Canagarajah, A. Suresh; Harklau, Linda; Hyland, Ken; Warschauer, Mark
This article is based on an invited colloqium on second language (L) writing presented at the 200 meeting of the American Association for Applied Linguistics. The colloquium featured five second language writing researchers two discussed some of the important currents that have shaped the field of second language writing. (Author/VWL)
Paired and Interacting Galaxies: International Astronomical Union Colloquium No. 124
NASA Technical Reports Server (NTRS)
Sulentic, Jack W. (Editor); Keel, William C. (Editor); Telesco, C. M. (Editor)
The proceedings of the International Astronomical Union Colloquium No. 124, held at the University of Alabama at Tuscaloosa, on December 4 to 7, are given. The purpose of the conference was to describe the current state of theoretical and observational knowledge of interacting galaxies, with particular emphasis on galaxies in pairs.
Codes, Ciphers, and Cryptography--An Honors Colloquium
ERIC Educational Resources Information Center
Karls, Michael A.
At the suggestion of a colleague, I read "The Code Book", [32], by Simon Singh to get a basic introduction to the RSA encryption scheme. Inspired by Singh's book, I designed a Ball State University Honors Colloquium in Mathematics for both majors and non-majors, with material coming from "The Code Book" and many other sources. This course became…
The Twenty-First NASTRAN (R) Users' Colloquium
NASA Technical Reports Server (NTRS)
This publication contains the proceedings of the Twenty-First NASTRAN Users' Colloquium held in Tampa, FL, April 26 through April 30, 1993. It provides some comprehensive general papers on the application of finite elements in engineering, comparisons with other approaches, unique applications, pre-and postprocessing with other auxiliary programs and new methods of analysis with NASTRAN.
Colloquium: Digital Technologies--Help or Hindrance for the Humanities?
ERIC Educational Resources Information Center
Barker, Elton; Bissell, Chris; Hardwick, Lorna; Jones, Allan; Ridge, Mia; Wolffe, John
This article offers reflections arising from a recent colloquium at the Open University on the implications of the development of digital humanities for research in arts disciplines, and also for their interactions with computing and technology. Particular issues explored include the ways in which the digital turn in humanities research is also a…
The Changing Role of the IAU in Providing and Organising Information
NASA Astrophysics Data System (ADS)
Batten, A. H.; McNally, D.
We discuss the way in which the IAU has organized information and supplied it to the astronomical community (with special reference to the Telegram Bureau), to students worldwide, to other international unions, to governments and inter-governmental organizations and to the general public.
Nominal Values for Selected Solar and Planetary Quantities: IAU 2015 Resolution B3
NASA Astrophysics Data System (ADS)
Prša, Andrej; Harmanec, Petr; Torres, Guillermo; Mamajek, Eric; Asplund, Martin; Capitaine, Nicole; Christensen-Dalsgaard, Jørgen; Depagne, Éric; Haberreiter, Margit; Hekker, Saskia; Hilton, James; Kopp, Greg; Kostov, Veselin; Kurtz, Donald W.; Laskar, Jacques; Mason, Brian D.; Milone, Eugene F.; Montgomery, Michele; Richards, Mercedes; Schmutz, Werner; Schou, Jesper; Stewart, Susan G.
In this brief communication we provide the rationale for and the outcome of the International Astronomical Union (IAU) resolution vote at the XXIXth General Assembly in Honolulu, Hawaii, in 2015, on recommended nominal conversion constants for selected solar and planetary properties. The problem addressed by the resolution is a lack of established conversion constants between solar and planetary values and SI units: a missing standard has caused a proliferation of solar values (e.g., solar radius, solar irradiance, solar luminosity, solar effective temperature, and solar mass parameter) in the literature, with cited solar values typically based on best estimates at the time of paper writing. As precision of observations increases, a set of consistent values becomes increasingly important. To address this, an IAU Working Group on Nominal Units for Stellar and Planetary Astronomy formed in 2011, uniting experts from the solar, stellar, planetary, exoplanetary, and fundamental astronomy, as well as from general standards fields to converge on optimal values for nominal conversion constants. The effort resulted in the IAU 2015 Resolution B3, passed at the IAU General Assembly by a large majority. The resolution recommends the use of nominal solar and planetary values, which are by definition exact and are expressed in SI units. These nominal values should be understood as conversion factors only, not as the true solar/planetary properties or current best estimates. Authors and journal editors are urged to join in using the standard values set forth by this resolution in future work and publications to help minimize further confusion.
An Analysis of Papers on Astronomy Education in Proceedings of IAU Meetings from 1988 to 2006
ERIC Educational Resources Information Center
Bretones, Paulo Sergio; Megid Neto, Jorge
The authors analyzed 283 papers dealing with astronomy education published in the IAU proceedings from 1988 to 2006. The analysis was conducted to determine both the characteristics and trends of published research studies in order to determine whether researchers should consider taking new directions. The authors conclude that educational…
Building on IYA2009: IAU Strategic Plan ``Astronomy for the Developing World''
NASA Astrophysics Data System (ADS)
Miley, George; Carignan, Claude; Govender, Kevin
During the next decade the IAU intends to mobilize talented astronomers, engineers and teachers around the world, in the service of developing countries. I shall review the content of the IAU Strategic Plan 2010 - 2020 ``Astronomy for the Developing World'' and give you an update on its implementation. Astronomy is a unique tool for stimulating capacity building because it combines cutting-edge technology with fundamental science and has deep cultural roots. The plan envisages a substantial increase in IAU education and development activities during the next decade. These activities will be bottom-up, with a strong regional influence. An integrated approach tailored to the conditions and needs of each country will involve a mix of education at primary, secondary and tertiary levels and public outreach. As a crucial component of the strategy, the IAU together with the South African National Research Foundation will set up a small office to coordinate and plan the various global activities at the SAAO in Cape Town.
Report on the 2015 COSPAR Panel on Planetary Protection Colloquium
NASA Astrophysics Data System (ADS)
Hipkin, Victoria; Kminek, Gerhard
In consultation with the COSPAR Scientific Commissions B (Space Studies of the Earth-Moon System, Planets, and Small Bodies of the Solar System) and F (Life Sciences as Related to Space), the COSPAR Panel on Planetary Protection organised a colloquium at the International Space Science Institute (ISSI) in Bern, Switzerland, in September 2015, to cover two pertinent topics: * Icy moon sample return planetary protection requirements * Mars Special Regions planetary protection requirements These two topics were addressed in two separate sessions. Participation from European, North American and Japanese scientists reflected broad expertise from the respective COSPAR Commissions, recent NASA MEPAG Science Analysis Group and National Academies of Sciences, Engineering, and Medicine/European Science Foundation Mars Special Regions Review Committee. The recommendations described in this report are based on discussions that took place during the course of the colloquium and reflect a consensus of the colloquium participants that participated in the two separate sessions. These recommendations are brought to the 2016 COSPAR Scientific Assembly for further input and discussion as part of the recognised process for updating COSPAR Planetary Protection Policy.
1984-2008. Predictions for Higher Education. From the 25th Anniversary Colloquium. [Proceedings].
ERIC Educational Resources Information Center
Hardee, Melvene Draheim, Ed.
Predictions on higher education for 1984-2009 are presented in the proceedings of a colloquium of the Institute for Studies in Higher Education of Florida State University. Presentations were made at the colloquium by 10 graduates of the university whose current positions represent administration-management, instruction, research, and student…
The IAU Division A Working Group on the Third Realization of the ICRF: Background, Goals, Plans
NASA Astrophysics Data System (ADS)
Gaume, Ralph
The XXVIII General Assembly of the IAU (Beijing, 2012) established the Division A Working Group on the Third Realization of the International Celestial Reference Frame (ICRF). The adopted charter of the ICRF3 Working Group includes a commitment to report on the implementation and execution plans for ICRF3 during the XXIX General Assembly of the IAU along with a targeted completion and presentation of ICRF3 in 2018 to the XXX General Assembly for adoption. This talk will discuss the background, purpose, and overall implementation plan for ICRF3, and motivate the concept, currently under consideration by the ICRF3 Working Group, that future realizations of the ICRF be based on multi-frequency astrometric data, starting with ICRF3.
In search of a viable IAU-OAD Regional Node: A case for Africa
NASA Astrophysics Data System (ADS)
Okere, B. I.; Okoh, D. C.; Obi, I. A.; Okeke, P. N.; Opara, F. E.
The establishment of the IAU Office of Astronomy for Development (OAD) in Cape Town, South Africa, with the aim of using astronomy to stimulate development at all levels including primary, secondary and tertiary education, science research and the public understanding of science is a welcome development to consolidate the gains of IYA2009. To assist the IAU OAD office in achieving its goal of using astronomy as a tool for development, there is need to have OAD regional nodes. In this paper, we present the astronomy activities/programs required of such a Regional Node in Africa and how the Node can play a significant role to realise the vision of Astronomy for a better world!
Waves and Oscillations in the Solar Atmosphere (IAU S247)
NASA Astrophysics Data System (ADS)
Erdélyi, Robert; Mendoza-Briceno, César A.
Preface; Organizing committee; Conference participants; Address by the Scientific Organizing Committee R. Erdélyi; Progress in coronal seismology B. Roberts; Session 1. Waves and oscillations in solar and stellar interior Robert Erdélyi; Session 2. Coupling of global solar and stellar motions into the lower atmosphere Bernard Roberts; Session 3. Seismology of the lower solar atmosphere and stellar chromospheres Siraj S. Hasan; Session 4. Seismology of open versus closed magnetic structures Marcel Goossens; Session 5. Prominence seismology Jose Luis Ballester; Session 6. Dynamical processes and coupling in the magnetic atmosphere of Sun and stars Miguel Ibañez; Session 7. Wave-particle interactions in magnetized plasmas Cesar A. Mendoza-Briceño; Session 8. Solar and stellar global coronal seismology Viggo Hansteen; Session 9. Fundamental physical processes in coronae: waves, turbulence, reconnection Saku Tsuneta; Session 10. Waves and instabilities in atmospheric plasmas Arnold O. Benz; Summary of meeting Cesar A. Mendoza-Briceño; Concluding remarks A. O. Benz; Late papers; Author index.
Papers presented to the International Colloquium on Venus
NASA Technical Reports Server (NTRS)
This volume contains short papers that have been accepted for the International Colloquium on Venus, August 10-12, Pasadena, California. The Program Committee consisted of Stephen Saunders (Jet Propulsion Laboratory) and Sean C. Solomon (Massachusetts Institute of Technology). Chairmen: Raymond Arvison (Washington University); Vassily Moroz (Institute for Space Research); Donald B. Campbell (Cornell University); Thomas Donahue (University of Michigan); James W. Head III (Brown University); Pamela Jones (Lunar and Planetary Institute); Mona Jasnow, Andrew Morrison, Timothy Pardker, Jeffrey Plaut, Ellen Stofan, Tommy Thompson, Cathy Weitz (Jet Propulsion Laboratory); Gordon Pettengil (Massachusetts Institute of Technology); and Janet Luhmann (University of California, Los Angeles).
News and Views: OAD establishes links; IAU General Assembly moves forward; Website collects astronomical heritage online; New national members; Inquiries of Heaven; Dark skies in Beijing
NASA Astrophysics Data System (ADS)
The 28th General Assembly of the International Astronomical Union in Beijing was an effective and enjoyable forum for presenting and discussing research, including the announcement of measures to preserve dark skies, rationalize definitions and units of measurement and a new focus on outreach for the IAU itself. The IAU GA saw the launch of a joint UNESCO-IAU project to bring the world's astronomical heritage to a wider audience.
Colloquium: 100 years of mass spectrometry: Perspectives and future trends
NASA Astrophysics Data System (ADS)
Maher, Simon; Jjunju, Fred P. M.; Taylor, Stephen
Mass spectrometry (MS) is widely regarded as the most sensitive and specific general purpose analytical technique. More than a century has passed for MS since the ground-breaking work of Nobel laureate Sir Joseph John Thomson in 1913. This Colloquium aims to (1) give an historical overview of the major instrumentation achievements that have driven mass spectrometry forward in the past century, including those leading up to the initial work of Thomson, (2) provide the nonspecialist with an introduction to MS, and (3) highlight some key applications of MS and explore the current and future trends. Because of the vastness of the subject area and quality of the manifold research efforts that have been undertaken over the last 100 years, which have contributed to the foundations and subsequent advances in mass spectrometry, it should be understood that not all of the key contributions may have been included in this Colloquium. Mass spectrometry has embraced a multitude of scientific disciplines and to recognize all of the achievements is an impossible task, such has been the diverse impact of this invaluable technique. Scientific progress is usually made via the cumulative effort of a large number of researchers; the achievements reported herein are only a representation of that effort.
Report of the IAU Working Group on cartographic coordinates and rotational elements: 2009
Archinal, B.A.; A'Hearn, M.F.; Bowell, E.; Conrad, A.; Consolmagno, G.J.; Courtin, R.; Fukushima, T.; Hestroffer, D.; Hilton, J.L.; Krasinsky, G.A.; Neumann, G.; Oberst, J.; Seidelmann, P.K.; Stooke, P.; Tholen, D.J.; Thomas, P.C.; Williams, I.P.
Every three years the IAU Working Group on Cartographic Coordinates and Rotational Elements revises tables giving the directions of the poles of rotation and the prime meridians of the planets, satellites, minor planets, and comets. This report takes into account the IAU Working Group for Planetary System Nomenclature (WGPSN) and the IAU Committee on Small Body Nomenclature (CSBN) definition of dwarf planets, introduces improved values for the pole and rotation rate of Mercury, returns the rotation rate of Jupiter to a previous value, introduces improved values for the rotation of five satellites of Saturn, and adds the equatorial radius of the Sun for comparison. It also adds or updates size and shape information for the Earth, Mars' satellites Deimos and Phobos, the four Galilean satellites of Jupiter, and 22 satellites of Saturn. Pole, rotation, and size information has been added for the asteroids (21) Lutetia, (511) Davida, and (2867) Šteins. Pole and rotation information has been added for (2) Pallas and (21) Lutetia. Pole and rotation and mean radius information has been added for (1) Ceres. Pole information has been updated for (4) Vesta. The high precision realization for the pole and rotation rate of the Moon is updated. Alternative orientation models for Mars, Jupiter, and Saturn are noted. The Working Group also reaffirms that once an observable feature at a defined longitude is chosen, a longitude definition origin should not change except under unusual circumstances. It is also noted that alternative coordinate systems may exist for various (e.g. dynamical) purposes, but specific cartographic coordinate system information continues to be recommended for each body. The Working Group elaborates on its purpose, and also announces its plans to occasionally provide limited updates to its recommendations via its website, in order to address community needs for some updates more often than every 3 years. Brief recommendations are also made to the general
Report of the IAU Working Group on Cartographic Coordinates and Rotational Elements: 2009
NASA Astrophysics Data System (ADS)
Archinal, B. A.; A'Hearn, M. F.; Bowell, E.; Conrad, A.; Consolmagno, G. J.; Courtin, R.; Fukushima, T.; Hestroffer, D.; Hilton, J. L.; Krasinsky, G. A.; Neumann, G.; Oberst, J.; Seidelmann, P. K.; Stooke, P.; Tholen, D. J.; Thomas, P. C.; Williams, I. P.
Every three years the IAU Working Group on Cartographic Coordinates and Rotational Elements revises tables giving the directions of the poles of rotation and the prime meridians of the planets, satellites, minor planets, and comets. This report takes into account the IAU Working Group for Planetary System Nomenclature (WGPSN) and the IAU Committee on Small Body Nomenclature (CSBN) definition of dwarf planets, introduces improved values for the pole and rotation rate of Mercury, returns the rotation rate of Jupiter to a previous value, introduces improved values for the rotation of five satellites of Saturn, and adds the equatorial radius of the Sun for comparison. It also adds or updates size and shape information for the Earth, Mars' satellites Deimos and Phobos, the four Galilean satellites of Jupiter, and 22 satellites of Saturn. Pole, rotation, and size information has been added for the asteroids (21) Lutetia, (511) Davida, and (2867) Šteins. Pole and rotation information has been added for (2) Pallas and (21) Lutetia. Pole and rotation and mean radius information has been added for (1) Ceres. Pole information has been updated for (4) Vesta. The high precision realization for the pole and rotation rate of the Moon is updated. Alternative orientation models for Mars, Jupiter, and Saturn are noted. The Working Group also reaffirms that once an observable feature at a defined longitude is chosen, a longitude definition origin should not change except under unusual circumstances. It is also noted that alternative coordinate systems may exist for various (e.g. dynamical) purposes, but specific cartographic coordinate system information continues to be recommended for each body. The Working Group elaborates on its purpose, and also announces its plans to occasionally provide limited updates to its recommendations via its website, in order to address community needs for some updates more often than every 3 years. Brief recommendations are also made to the general
The Establishment of an Astrophysics Course in the Philippines through the IAU TAD
NASA Astrophysics Data System (ADS)
Celebre, C. P.
The Japanese Government through its Cultural Grant-aid Program, donated a 45-cm telescope to the Government of the Philippines. It was installed at the PAGASA Astronomical Observatory in May 2000. Its installation had made the officials of PAGASA realize the need to establish an undergraduate astrophysics course in the country. The course will be more economical and practical, compared to training courses and fellowships requested from abroad. It was planned to be established in cooperation with the IAU-TAD and the National Institute of Physics of the University of the Philippines. The activity is discussed in detail in this paper.
Nutation model (IAU 1980) and the corrections of its main terms from BLZ and PIP data.
NASA Astrophysics Data System (ADS)
Damljanović, G.; de Biasi, M. S.
The star observations of the Belgrade visual zenith telescope (in the list of Bureau International de l'Heure (BIH) series denoted by BLZ) for the period 1960 - 1985 (about 26 years of latitude data) and the Punta Indio photographic zenith tube (denoted by PIP) for the period 1971 - 1984 (about 14 years of latitude data) were used to obtain the correction (ΔN) to the amplitude of long periodic 18.6 years nutation obliquity term. The least-square method (LSQ) was applied. The reduction of both BLZ and PIP data was in line with the IAU 1980 Nutation Model.
Protection of Northern Chile as an ICOMOS/IAU ``Window to the Universe''
NASA Astrophysics Data System (ADS)
Smith, Malcolm G.
Over the last two decades, La Serena's population has increased by about 70 percent. A site description of the AURA Observatory in Chile as a ``Window to the Universe`` is now available on the recently-launched UNESCO-IAU Astronomical Heritage Web Portal, www.astronomicalheritage.net This can serve as an example of possible material for the Chilean authorities, should they wish to propose the dark skies over much of northern Chile for protection as a World Scientific Heritage site. Some of the steps involved are discussed briefly here.
Dynamics of localized disturbances in engineering flows: a report on Euromech Colloquium 353
NASA Astrophysics Data System (ADS)
Delfs, Jan; Oertel, Herbert, Jr.
Euromech Colloquium 353, held at the University of Karlsruhe, Germany, 1 3 April 1996 brought together scientists working in the field of localized disturbances of flows in order to discuss new developments and the potential for application. The colloquium attracted a total of 56 participants from nine European countries, i.e. France, Germany, The Netherlands, Poland, Russia, Sweden, Switzerland, Ukraine and United Kingdom as well as from the US and Israel.
Implementation of IAU Resolution 2009 B5, "in Defence of the night sky and the right to starlight"
NASA Astrophysics Data System (ADS)
Green, Richard F.; Walker, Constance Elaine
IAU Resolution 2009 B5 calls on IAU members to protect the public`s right to an unpolluted night sky as well as the astronomical quality of the sky around major research observatories. The approach of Commission 50 - astronomical site protection - includes working with the lighting industry for appropriate products from rapidly evolving solid state technology, arming astronomers with training and materials for presentation, selective endorsement of key protection issues, cooperation with other IAU commissions for education and outreach with particular current attention to the International Year of Light, and provision of clear quantitative priorities for outdoor lighting standards. In 2012, these priorities were defined as full cut-off shielding, spectral management to minimize output shortward of 500 nm, and zone- and time-appropriate lighting levels. Revisiting the specifics of these priorities will be a topic for current discussion.
Consistency Problems in the Improvement of the IAU Precession-Nutation Theories: Effects of the Dynamical Ellipticity Differences
NASA Astrophysics Data System (ADS)
Escapa, Alberto; Ferrándiz, José M.; Baenas, Tomás; Getino, Juan; Navarro, Juan F.; Belda-Palazón, Santiago
The complexity of the modeling of the rotational motion of the Earth in space has produced that no single theory has been adopted to describe it in full. Hence, it is customary using at least a theory for precession and another one for nutation. The classic approach proceeds by deriving some of the fundamental parameters from the precession theory, like, e.g., the dynamical ellipticity Hd, and then using those values in the nutation theory. The former IAU 1976 precession and IAU 1980 nutation theories followed that scheme. Along with the improvement of the accuracy of the determination of Earth orientation parameters, IAU 1980 was superseded by IAU2000, based on the application of the MHB2000 transfer function to the previous rigid Earth analytical theory REN2000. The latter was derived while the precession model IAU 1976 was still in force, therefore it used the corresponding values for some of the fundamental parameters, as the precession rate, associated to the dynamical ellipticity. The new precession model P03 was adopted as IAU 2006. That change introduced some inconsistency since P03 used different values for some of the fundamental parameters that MHB2000 inherited from REN2000. Besides, the derivation of the basic Earth parameters of MHB2000 itself comprised a fitted variation of the dynamical ellipticity adopted in the background rigid theory. Due to the strict requirements of accuracy of the present and coming times, the magnitude of the inconsistencies originated by this twofold approach is no longer negligible as earlier, hence the need of discussing the effects of considering slightly different values for H_d in precession and nutation theories.
Confirmation and characterization of IAU temporary meteor showers in EDMOND database
NASA Astrophysics Data System (ADS)
Kornoš, L.; Matlovič, P.; Rudawska, R.; Tóth, J.; Hajduková, M., Jr.; Koukal, J.; Piffl, R.
The European viDeo MeteOr Network Database (EDMOND) is a database of video meteor orbits resulting from cooperation and data sharing among several European national networks and the International Meteor Organization Video Meteor Network, IMO VMN, (Kornosš et al., 2014, Proc. IMC 2013). At present, the 4th version of the EDMOND database, which contains 83369 video meteor orbits, has been released. The first results of the database analysis, in which we studied minor streams, are presented. Using the radiant-geocentric velocity method we identified 267 meteor showers, among them 67 established showers and 200 from the working list of the IAU MDC. Making a more detailed examination, we clearly identified 22 showers of 65 pro tempore showers of the working list of the IAU MDC (updated in August 2013). The identification of 18 meteor showers was questionable, while 25 showers were not found. For all the identified temporary meteor showers, we list the weighted mean orbital elements, the radiant position and the geocentric velocity.
Universality, Diversity, Interdependence: The Missions of IAU. Policy Outline 1990-1995. International Association of Universities General Conference (9th, Helsinki, Finland, August 5-11, 1990).
ERIC Educational Resources Information Center
International Association of Universities, Paris (France).
This policy outline was issued to guide the work of the International Association of Universities (IAU) as it develops policy for the further development of services, outreach, and partnerships. Services being rendered or developed by IAU's International Universities Bureau are described to provide a departure point for policy considerations.…
Colloquium: Statistical mechanics of money, wealth, and income
NASA Astrophysics Data System (ADS)
Yakovenko, Victor M.; Rosser, J. Barkley, Jr.
This Colloquium reviews statistical models for money, wealth, and income distributions developed in the econophysics literature since the late 1990s. By analogy with the Boltzmann-Gibbs distribution of energy in physics, it is shown that the probability distribution of money is exponential for certain classes of models with interacting economic agents. Alternative scenarios are also reviewed. Data analysis of the empirical distributions of wealth and income reveals a two-class distribution. The majority of the population belongs to the lower class, characterized by the exponential ("thermal") distribution, whereas a small fraction of the population in the upper class is characterized by the power-law ("superthermal") distribution. The lower part is very stable, stationary in time, whereas the upper part is highly dynamical and out of equilibrium.
Colloquium: Geometry and optimal packing of twisted columns and filaments
NASA Astrophysics Data System (ADS)
Grason, Gregory M.
This Colloquium presents recent progress in understanding constraints and consequences of close-packing geometry of filamentous or columnar materials possessing nontrivial textures, focusing, in particular, on the common motifs of twisted and toroidal structures. The mathematical framework is presented that relates spacing between linelike, filamentous elements to their backbone orientations, highlighting the explicit connection between the interfilament metric properties and the geometry of non-Euclidean surfaces. The consequences of the hidden connection between packing in twisted filament bundles and packing on positively curved surfaces, like the Thomson problem, are demonstrated for the defect-riddled ground states of physical models of twisted filament bundles. The connection between the "ideal" geometry of fibrations of curved three-dimensional space, including the Hopf fibration, and the non-Euclidean constraints of filament packing in twisted and toroidal bundles is presented, with a focus on the broader dependence of metric geometry on the simultaneous twisting and folding of multifilament bundles.
Report of the IAU Working Group on cartographic coordinates and rotational elements: 2009
Archinal, Brent A.; A'Hearn, Michael F.; Bowell, Edward; Conrad, Al; Consolmagno, Guy J.; Courtin, Regis; Fukushima, Toshio; Hestroffer, Daniel; Hilton, James L.; Krasinsky, Georgij A.; Neumann, Gregory; Oberst, Jurgen; Seidelmann, P. Kenneth; Stooke, Philip; Tholen, David J.; Thomas, Peter C.; Williams, Iwan P.
Every three years the IAU Working Group on Cartographic Coordinates and Rotational Elements revises tables giving the directions of the poles of rotation and the prime meridians of the planets, satellites, minor planets, and comets. This report takes into account the IAU Working Group for Planetary System Nomenclature (WGPSN) and the IAU Committee on Small Body Nomenclature (CSBN) definition of dwarf planets, introduces improved values for the pole and rotation rate of Mercury, returns the rotation rate of Jupiter to a previous value, introduces improved values for the rotation of five satellites of Saturn, and adds the equatorial radius of the Sun for comparison. It also adds or updates size and shape information for the Earth, Mars' satellites Deimos and Phobos, the four Galilean satellites of Jupiter, and 22 satellites of Saturn. Pole, rotation, and size information has been added for the asteroids (21) Lutetia, (511) Davida, and (2867) Šteins. Pole and rotation information has been added for (2) Pallas and (21) Lutetia. Pole and rotation and mean radius information has been added for (1) Ceres. Pole information has been updated for (4) Vesta. The high precision realization for the pole and rotation rate of the Moon is updated. Alternative orientation models for Mars, Jupiter, and Saturn are noted. The Working Group also reaffirms that once an observable feature at a defined longitude is chosen, a longitude definition origin should not change except under unusual circumstances. It is also noted that alternative coordinate systems may exist for various (e.g. dynamical) purposes, but specific cartographic coordinate system information continues to be recommended for each body. The Working Group elaborates on its purpose, and also announces its plans to occasionally provide limited updates to its recommendations via its website, in order to address community needs for some updates more often than every 3 years. Brief recommendations are also made to the
Report on the international colloquium on cardio-oncology (rome, 12-14 march 2014).
Ewer, Michael; Gianni, Luca; Pane, Fabrizio; Sandri, Maria Teresa; Steiner, Rudolf K; Wojnowski, Leszek; Yeh, Edward T; Carver, Joseph R; Lipshultz, Steven E; Minotti, Giorgio; Armstrong, Gregory T; Cardinale, Daniela; Colan, Steven D; Darby, Sarah C; Force, Thomas L; Kremer, Leontien Cm; Lenihan, Daniel J; Sallan, Stephen E; Sawyer, Douglas B; Suter, Thomas M; Swain, Sandra M; van Leeuwen, Flora E
Cardio-oncology is a relatively new discipline that focuses on the cardiovascular sequelae of anti-tumour drugs. As any other young adolescent discipline, cardio-oncology struggles to define its scientific boundaries and to identify best standards of care for cancer patients or survivors at risk of cardiovascular events. The International Colloquium on Cardio-Oncology was held in Rome, Italy, 12-14 March 2014, with the aim of illuminating controversial issues and unmet needs in modern cardio-oncology. This colloquium embraced contributions from different kind of disciplines (oncology and cardiology but also paediatrics, geriatrics, genetics, and translational research); in fact, cardio-oncology goes way beyond the merging of cardiology with oncology. Moreover, the colloquium programme did not review cardiovascular toxicity from one drug or the other, rather it looked at patients as we see them in their fight against cancer and eventually returning to everyday life. This represents the melting pot in which anti-cancer therapies, genetic backgrounds, and risk factors conspire in producing cardiovascular sequelae, and this calls for screening programmes and well-designed platforms of collaboration between one key professional figure and another. The International Colloquium on Cardio-Oncology was promoted by the Menarini International Foundation and co-chaired by Giorgio Minotti (Rome), Joseph R Carver (Philadelphia, Pennsylvania, United States), and Steven E Lipshultz (Detroit, Michigan, United States). The programme was split into five sessions of broad investigational and clinical relevance (what is cardiotoxicity?, cardiotoxicity in children, adolescents, and young adults, cardiotoxicity in adults, cardiotoxicity in special populations, and the future of cardio-oncology). Here, the colloquium chairs and all the session chairs briefly summarised what was said at the colloquium. Topics and controversies were reported on behalf of all members of the working group of
Report on the International Colloquium on Cardio-Oncology (Rome, 12–14 March 2014)
Ewer, Michael; Gianni, Luca; Pane, Fabrizio; Sandri, Maria Teresa; Steiner, Rudolf K; Wojnowski, Leszek; Yeh, Edward T; Carver, Joseph R; Lipshultz, Steven E; Minotti, Giorgio; Armstrong, Gregory T; Cardinale, Daniela; Colan, Steven D; Darby, Sarah C; Force, Thomas L; Kremer, Leontien CM; Lenihan, Daniel J; Sallan, Stephen E; Sawyer, Douglas B; Suter, Thomas M; Swain, Sandra M; van Leeuwen, Flora E
Cardio-oncology is a relatively new discipline that focuses on the cardiovascular sequelae of anti-tumour drugs. As any other young adolescent discipline, cardio-oncology struggles to define its scientific boundaries and to identify best standards of care for cancer patients or survivors at risk of cardiovascular events. The International Colloquium on Cardio-Oncology was held in Rome, Italy, 12–14 March 2014, with the aim of illuminating controversial issues and unmet needs in modern cardio-oncology. This colloquium embraced contributions from different kind of disciplines (oncology and cardiology but also paediatrics, geriatrics, genetics, and translational research); in fact, cardio-oncology goes way beyond the merging of cardiology with oncology. Moreover, the colloquium programme did not review cardiovascular toxicity from one drug or the other, rather it looked at patients as we see them in their fight against cancer and eventually returning to everyday life. This represents the melting pot in which anti-cancer therapies, genetic backgrounds, and risk factors conspire in producing cardiovascular sequelae, and this calls for screening programmes and well-designed platforms of collaboration between one key professional figure and another. The International Colloquium on Cardio-Oncology was promoted by the Menarini International Foundation and co-chaired by Giorgio Minotti (Rome), Joseph R Carver (Philadelphia, Pennsylvania, United States), and Steven E Lipshultz (Detroit, Michigan, United States). The programme was split into five sessions of broad investigational and clinical relevance (what is cardiotoxicity?, cardiotoxicity in children, adolescents, and young adults, cardiotoxicity in adults, cardiotoxicity in special populations, and the future of cardio-oncology). Here, the colloquium chairs and all the session chairs briefly summarised what was said at the colloquium. Topics and controversies were reported on behalf of all members of the working group
The Goal of the IAU/IAG Joint Working Group on the Theory of Earth Rotation
NASA Technical Reports Server (NTRS)
Ferrandiz, J. M.; Gross, R. S.
In 2012 the International Association of Geodesy (IAG) and the International Astronomical Union (IAU) initiated a process to establish a Joint Working Group (JWG) on theory of Earth rotation with the purpose of promoting the development of improved theories of the Earth rotation which reach the accuracy required to meet the needs of the near future as recommended by, e.g. GGOS, the Global Geodetic Observing System of the IAG. The JWG was approved by both organizations in April 2013 with the chairs being the two authors of this paper. Its structure comprises three Sub Working Groups (SWGs) addressing Precession/Nutation, Polar Motion and UT1, the Numerical Solutions and Validation, respectively. The SWGs should work in parallel for the sake of efficiency, but should keep consistency as an overall goal. This paper offers a view of the objectives and scope of the JWG and reports about its initial activities and plans.
Report of the IAU/IAG Working Group on cartographic coordinates and rotational elements: 2006
Seidelmann, P.K.; Archinal, B.A.; A'Hearn, M.F.; Conrad, A.; Consolmagno, G.J.; Hestroffer, D.; Hilton, J.L.; Krasinsky, G.A.; Neumann, G.; Oberst, J.; Stooke, P.; Tedesco, E.F.; Tholen, D.J.; Thomas, P.C.; Williams, I.P.
Every three years the IAU/IAG Working Group on Cartographic Coordinates and Rotational Elements revises tables giving the directions of the poles of rotation and the prime meridians of the planets, satellites, minor planets, and comets. This report introduces improved values for the pole and rotation rate of Pluto, Charon, and Phoebe, the pole of Jupiter, the sizes and shapes of Saturn satellites and Charon, and the poles, rotation rates, and sizes of some minor planets and comets. A high precision realization for the pole and rotation rate of the Moon is provided. The expression for the Sun's rotation has been changed to be consistent with the planets and to account for light travel time ?? 2007 Springer Science+Business Media B.V.
Washington Colloquium on Science and Society, Second Series (Held at Georgetown University, Washington, D.C. 1965-1966).
ERIC Educational Resources Information Center
Leeds, Morton, Ed.
This is the report of the third Washington Colloquium on Science and Society. It contains the papers presented by the eight main speakers and the rebuttal and discussion which followed. The theme of the colloquium was "Changing Man in a Changing Environment," and the papers presented aspects of this theme as seen by different specialists in…
Main Objectives for this I.A.U. Special Session on Innovation in Teaching/ Learning Astronomy
NASA Astrophysics Data System (ADS)
Pasachoff, J. M.; Ros, R. M.
In the IAU resolution on the Value of Astronomy Education, passed by the IAU's General Assembly in 2003, it was recommended: to include astronomy in school curricula, to assist schoolteachers in their training and backup, and to inform teachers about available resources. The aim of this Special Session 2 on "Innovation in Teaching/Learning Astronomy" is to contribute to the implementation of these recommendations, introducing innovative points of view regarding methods of teaching and learning. Astronomers from all countries—developed or developing—will be equally interested. New methods of dissemination of information are making big changes in the opportunity of spreading astronomical knowledge. The World Wide Web continues to expand its reach, and the Astronomy Picture of the Day reaches the homepage of millions. The new phenomenon of podcasts is spreading rapidly. Astronomy attracts many young people to education in important fields in science and technology. But in many countries, astronomy is not part of the standard curriculum, and teachers do not receive adequate education and support. Still, many scientific and educational societies and government agencies have produced materials and educational resources in astronomy for all educational levels. Technology is used in astronomy both for obtaining observations and for teaching. In any case, it is useful to take their special opportunity to learn about the situation in different countries, to exchange opinions, and to collect information in order to continue, over at least the next triennium, the activities related to promoting astronomy throughout the world. In particular, we would like to invite all participants to explain their positive original experiences so they can be adapted for other regions. Everyone is invited to exchange their initiatives and to try to involve other countries in common projects. All of us are in the same boat. http://www.communicatingastronomy.org/innovation2006/
Report of the COSPAR mars special regions colloquium
Kminek, G.; Rummel, J.D.; Cockell, C.S.; Atlas, R.; Barlow, N.; Beaty, D.; Boynton, W.; Carr, M.; Clifford, S.; Conley, C.A.; Davila, A.F.; Debus, A.; Doran, P.; Hecht, M.; Heldmann, J.; Helbert, J.; Hipkin, V.; Horneck, G.; Kieft, Thomas L.; Klingelhoefer, G.; Meyer, M.; Newsom, H.; Ori, G.G.; Parnell, J.; Prieur, D.; Raulin, F.; Schulze-Makuch, D.; Spry, J.A.; Stabekis, P.E.; Stackebrandt, E.; Vago, J.; Viso, M.; Voytek, M.; Wells, L.; Westall, F.
In this paper we present the findings of a COSPAR Mars Special Regions Colloquium held in Rome in 2007. We review and discuss the definition of Mars Special Regions, the physical parameters used to define Mars Special Regions, and physical features on Mars that can be interpreted as Mars Special Regions. We conclude that any region experiencing temperatures > -25 ??C for a few hours a year and a water activity > 0.5 can potentially allow the replication of terrestrial microorganisms. Physical features on Mars that can be interpreted as meeting these conditions constitute a Mars Special Region. Based on current knowledge of the martian environment and the conservative nature of planetary protection, the following features constitute Mars Special regions: Gullies and bright streaks associated with them, pasted-on terrain, deep subsurface, dark streaks only on a case-by-case basis, others to be determined. The parameter definition and the associated list of physical features should be re-evaluated on a regular basis. ?? 2010 COSPAR. Published by Elsevier Ltd. All rights reserved.
Colloquium: Physical approaches to DNA sequencing and detection
NASA Astrophysics Data System (ADS)
Zwolak, Michael; di Ventra, Massimiliano
With the continued improvement of sequencing technologies, the prospect of genome-based medicine is now at the forefront of scientific research. To realize this potential, however, a revolutionary sequencing method is needed for the cost-effective and rapid interrogation of individual genomes. This capability is likely to be provided by a physical approach to probing DNA at the single-nucleotide level. This is in sharp contrast to current techniques and instruments that probe (through chemical elongation, electrophoresis, and optical detection) length differences and terminating bases of strands of DNA. Several physical approaches to DNA detection have the potential to deliver fast and low-cost sequencing. Central to these approaches is the concept of nanochannels or nanopores, which allow for the spatial confinement of DNA molecules. In addition to their possible impact in medicine and biology, the methods offer ideal test beds to study open scientific issues and challenges in the relatively unexplored area at the interface between solids, liquids, and biomolecules at the nanometer length scale. This Colloquium emphasizes the physics behind these methods and ideas, critically describes their advantages and drawbacks, and discusses future research opportunities in the field.
Colloquium: Fractional calculus view of complexity: A tutorial
NASA Astrophysics Data System (ADS)
West, Bruce J.
The fractional calculus has been part of the mathematics and science literature for 310 years. However, it is only in the past decade or so that it has drawn the attention of mainstream science as a way to describe the dynamics of complex phenomena with long-term memory, spatial heterogeneity, along with nonstationary and nonergodic statistics. The most recent application encompasses complex networks, which require new ways of thinking about the world. Part of the new cognition is provided by the fractional calculus description of temporal and topological complexity. Consequently, this Colloquium is not so much a tutorial on the mathematics of the fractional calculus as it is an exploration of how complex phenomena in the physical, social, and life sciences that have eluded traditional mathematical modeling become less mysterious when certain historical assumptions such as differentiability are discarded and the ordinary calculus is replaced with the fractional calculus. Exemplars considered include the fractional differential equations describing the dynamics of viscoelastic materials, turbulence, foraging, and phase transitions in complex social networks.
Report of the proceedings of the Colloquium and Workshop on Multiscale Coupled Modeling
NASA Technical Reports Server (NTRS)
Koch, Steven E. (Editor)
The Colloquium and Workshop on Multiscale Coupled Modeling was held for the purpose of addressing modeling issues of importance to planning for the Cooperative Multiscale Experiment (CME). The colloquium presentations attempted to assess the current ability of numerical models to accurately simulate the development and evolution of mesoscale cloud and precipitation systems and their cycling of water substance, energy, and trace species. The primary purpose of the workshop was to make specific recommendations for the improvement of mesoscale models prior to the CME, their coupling with cloud, cumulus ensemble, hydrology, air chemistry models, and the observational requirements to initialize and verify these models.
Final Update of the IAU Commission 4 Working Group on Standardizing Access to Ephemerides and File Format Specification
NASA Astrophysics Data System (ADS)
Hilton, James L.
The IAU Commission 4 Working Group on Standardizing Access to Ephemerides recommends the use of the Spacecraft and Planet Kernel (SPK) format to provide a uniform format for the position ephemerides of planets and other natural solar system bodies, and the use of the Planetary Constants Kernel (PCK) for the orientation of these bodies. These formats are used by the SPICE system, developed by the Navigation and Ancillary Information Facility of NASA's Jet Propulsion Laboratory. The working group's final report is currently undergoing final preparations for publication. A long version of this report will be available at the IAU Commission 4 - Ephemerides (or its successor) web site. This long version will contain a full description of that portion of the SPK and PCK formats required to duplicate these file types for this application.
Report on the ESO/OPTICON/IAU Summer School ''Modern Instruments, their Science Case, and Practical Data Reduction''
NASA Astrophysics Data System (ADS)
Kabath, P.; Dennefeld, M.; Gerbaldi, M.; Paunzen, E.; Karas, V.
The Astronomical Institute of the Czech Academy of Sciences organised, jointly with its local partners from Masaryk University, and international partners OPTICON, ESO and the IAU, a two-week practical training course in astronomy for young researchers. The summer school is briefly summarised: lectures covered a wide range of theoretical and observational topics and the emphasis of the practical work was on the analysis of archival data.
Adaptive auditory feedback control of the production of formant trajectories in the Mandarin triphthong /iau/ and its pattern of generalization.
Cai, Shanqing; Ghosh, Satrajit S; Guenther, Frank H; Perkell, Joseph S
In order to test whether auditory feedback is involved in the planning of complex articulatory gestures in time-varying phonemes, the current study examined native Mandarin speakers' responses to auditory perturbations of their auditory feedback of the trajectory of the first formant frequency during their production of the triphthong /iau/. On average, subjects adaptively adjusted their productions to partially compensate for the perturbations in auditory feedback. This result indicates that auditory feedback control of speech movements is not restricted to quasi-static gestures in monophthongs as found in previous studies, but also extends to time-varying gestures. To probe the internal structure of the mechanisms of auditory-motor transformations, the pattern of generalization of the adaptation learned on the triphthong /iau/ to other vowels with different temporal and spatial characteristics (produced only under masking noise) was tested. A broad but weak pattern of generalization was observed; the strength of the generalization diminished with increasing dissimilarity from /iau/. The details and implications of the pattern of generalization are examined and discussed in light of previous sensorimotor adaptation studies of both speech and limb motor control and a neurocomputational model of speech motor control. PMID:20968374
IAU Working Group on International Data Access for Solar and Heliospheric data
NASA Astrophysics Data System (ADS)
Bentley, R. D.; Hill, F.; Hurlburt, N.; Roberts, A.
Division II (Sun and Heliosphere) of the IAU has initiated a Working Group to study the archiving, retrieval and distribution of solar and heliospheric data. The goal of the Working Group is to facilitate the use of available solar and heliospheric data that are archived in a large number of computers scattered all over the world. The intent of the Working Group is to help coordinate the existing and growing data exchange through the Internet and work with the virtual observatory initiatives to propose guidelines for exchange at an international level and encourage participation in the projects. The Working Group is working with the virtual observatory initiatives to ensure that they develop standards and employ techniques that are acceptable to the worldwide solar and heliospheric communities and to encourage interoperability between the projects. The EGSO, VSO, CoSEC and VSPO projects are all part of the Working Group and would also like to encourage the communities to help develop standards and participate in the virtual observatory projects. The aims of and objectives the Working Group will be discussed and feedback from the audience is encouraged.
Recent activities in Armenia related to IAU ROAD and strategic plan
NASA Astrophysics Data System (ADS)
Mickaelian, Areg M.
Armenia is one of the candidates to host a Regional Office of Astronomy for Development (ROAD), namely in the Middle East region. Armenia is a county of ancient astronomy and is also rich in modern astronomical facilities and infrastructures, hence may serve as a regional center for various activities. Recently we have conducted a number of new activities related to astronomy for development. A meeting "Relation of Astronomy to other Sciences, Culture and Society" (RASCS) was organized by Byurakan Astrophysical Observatory (BAO) and Armenian Astronomical Society (ArAS) in Oct 2014 in Byurakan. Astronomers, philosophers, biologists, historians, archaeologists, philologists, linguists, artists, and other specialists took part in the meeting. The meeting was important from the point of view of increasing the visibility of astronomy as a leader in interdisciplinary and multidisciplinary sciences. Activities related to Archaeoastronomy and Astronomy in Culture (AAC), as encouraged by a number of international organizations (UNESCO, IAU, ISAAC, SEAC, etc.), were initiated as well. Armenia is especially rich in astronomical heritage issues and this area may strongly support the ROAD project. Discussions on the future Armenian-Iranian collaboration in astronomy were carried out, including an Armenian-Iranian Astronomical Workshop to be held in Oct 2015 in Byurakan.
The IAU2000 Standards: The Newly Adopted Time, Coordinates, and Reference Frames.
NASA Astrophysics Data System (ADS)
Standish, E. M.
Over the past dozen years or so, the IAU has been deluged with resolutions from Division I (Fundamental Astronomy) regarding dynamics, reference frames, fundamental time-scales, earth orientation, etc. Some of the resolutions are merely cosmetic in nature, detailing the basic foundations which have been used by serious researchers for many years. Some of the other resolutions, however, will have a direct affect upon a number of different fields of study. Sooner or later, these changes will actually be implemented, and they will affect anyone doing precision-type work in astronomy, geophysics, and related fields. As with most changes, there are pros and cons; these will be discussed. On a more practical level, the following questions will be addressed: What major areas of astrometry will be affected? What specific items will change? What does one need to know in order to survive the changes? What does one have to do in order to not be adversely affected? The research described in this publication was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.
Colloquium: Non-Markovian dynamics in open quantum systems
NASA Astrophysics Data System (ADS)
Breuer, Heinz-Peter; Laine, Elsi-Mari; Piilo, Jyrki; Vacchini, Bassano
The dynamical behavior of open quantum systems plays a key role in many applications of quantum mechanics, examples ranging from fundamental problems, such as the environment-induced decay of quantum coherence and relaxation in many-body systems, to applications in condensed matter theory, quantum transport, quantum chemistry, and quantum information. In close analogy to a classical Markovian stochastic process, the interaction of an open quantum system with a noisy environment is often modeled phenomenologically by means of a dynamical semigroup with a corresponding time-independent generator in Lindblad form, which describes a memoryless dynamics of the open system typically leading to an irreversible loss of characteristic quantum features. However, in many applications open systems exhibit pronounced memory effects and a revival of genuine quantum properties such as quantum coherence, correlations, and entanglement. Here recent theoretical results on the rich non-Markovian quantum dynamics of open systems are discussed, paying particular attention to the rigorous mathematical definition, to the physical interpretation and classification, as well as to the quantification of quantum memory effects. The general theory is illustrated by a series of physical examples. The analysis reveals that memory effects of the open system dynamics reflect characteristic features of the environment which opens a new perspective for applications, namely, to exploit a small open system as a quantum probe signifying nontrivial features of the environment it is interacting with. This Colloquium further explores the various physical sources of non-Markovian quantum dynamics, such as structured environmental spectral densities, nonlocal correlations between environmental degrees of freedom, and correlations in the initial system-environment state, in addition to developing schemes for their local detection. Recent experiments addressing the detection, quantification, and control of
The Proceedings for the Colloquium on Diversity in Education Abroad: How to Change the Picture
ERIC Educational Resources Information Center
Herrin, Carl A., Ed.; Dadzie, Suzanne, Ed.; MacDonald, Sandra A., Ed.
The Academy for Educational Development (AED) Colloquium on Diversity in Education Abroad: How to Change the Picture was conceived of as a collaborative effort between the speakers, presenters, and participants. This publication presents the papers presented by the speakers. These are: (1) What We Know about Diversity in Education Abroad: State of…
Colloquium--Toward a Reconceptualization of "Language" and "Acquisition" in SLA Research
ERIC Educational Resources Information Center
Hellermann, John; Olsher, David
Held at the American Association for Applied Linguistics Annual Conference, Denver, CO, USA; 21 March 2009. This all-day colloquium was part of an ongoing discussion of ways that methods and frameworks from micro-ethnography, Conversation Analysis (CA), and Vygotskian Sociocultural Theory are re-specifying "language" and "acquisition" from a…
A Colloquium on Environment, Ethics, and Education (Whitehorse, Yukon, Canada, July 14-16, 1995).
ERIC Educational Resources Information Center
Jickling, Bob, Ed.
The papers in this proceedings explore two themes: "what environmental ethics can do for teachers," and "what teachers can do for environmental ethics." The papers are: "A Colloquium on Environment, Ethics, and Education: Considering the Context" (Bob Jickling); "Planning for the Future: Workshop Observations and Recommendations" (Colloquium…
Proceedings of the Fourth Annual Colloquium. Crisis, Challenge, and Change: Perspectives in Education.
ERIC Educational Resources Information Center
Pittsburgh Univ., PA. Council of Graduate Students in Education.
Graduate students and faculty from within and outside of the University of Pittsburgh community were among the presenters at this colloquium on educational change and challenge. The papers include: Academic Freedom, Anti-Communism, and the McCarthy Era (Steve Aby); The Finnish Contribution to the American Workers' Education Movement (Richard J.…
Invited Colloquium on Negotiating the Complexities of Multilingual Assessment, AAAL Conference 2014
ERIC Educational Resources Information Center
Menken, Kate; Shohamy, Elana
The invited colloquium on New Directions in Language Assessment held at the American Association for Applied Linguistics (AAAL) annual meeting in Portland, Oregon on March 22, 2014 brought together an international panel of scholars to together explore the possibilities and challenges of translanguaging and bi/multilingual approaches in…
EDITORIAL: Selected papers from the 19th International Colloquium on Magnetic Films and Surfaces
NASA Astrophysics Data System (ADS)
Miyazaki, T.; Inoue, J.
The 19th International Colloquium on Magnetic Films and Surfaces (ICMFS 2006) was held on 14-18 August 2006 at the Sendai International Center in Sendai, Japan. The purpose of the Colloquium was to bring together scientists working on magnetic thin films and surfaces and to provide an opportunity for presentation and discussion of recent experimental and theoretical advances in the field. 285 scientists from 17 countries (Japan: 167, overseas: 118) participated in the Colloquium, as well as 6 family members. There were 56 oral and 178 poster presentations. The oral presentations consisted of 3 plenary talks, 23 invited talks and 30 contributed talks. The number of presentations by scientific category are as follows: Spin dependent transport: 43 Magnetic storage/memory: 9 Magnetization reversal and fast dynamics: 15 Spin injection and spin transfer torque: 26 Magnetic thin films and multilayers: 71 High spin polarization materials: 17 Hard and soft magnetic materials: 3 Magneto-optics: 5 Characterization techniques for thin films and surfaces: 7 Exchange coupling: 13 Micro- and nanopatterned magnetic structures: 18 Micromagnetic modelling: 2 One of the characteristics of the present Colloquium is an increase in the number of presentations in the field of spin-electronics, as seen above. This Cluster Issue of Journal of Physics D: Applied Physics includes several important papers in this rapidly developing field. We believe that, in the future, the field of magnetic materials will maintain its popularity and, on top of that, other fields such as spintronics materials, materials related to life sciences and medicine and also materials related to the environment will be investigated further. The ICMFS Conference started in London in 1964, and is now one of the world-wide conferences on magnetism. The Colloquium has been held in Japan four times now: the previous ones being the 5th ICMFS in the Mount Fuji area, the 10th at Yokohama and the 17th at Kyoto, which was
Astronomy development in Serbia in view of the IAU Strategic Plan
NASA Astrophysics Data System (ADS)
Atanacković, Olga
An overview of astronomy development in Serbia in view of the goals envisaged by the IAU Strategic Plan is given. Due attention is paid to the recent reform of education at all levels. In the primary schools several extra topics in astronomy are introduced in the physics course. Attempts are made to reintroduce astronomy as a separate subject in the secondary schools. Special emphasis is put to the role and activities of the Petnica Science Center the biggest center for informal education in SE Europe, and to a successful participation of the Serbian team in International astronomy olympiads. Astronomy topics are taught at all five state universities in Serbia. At the University of Belgrade and Novi Sad students can enroll in astronomy from the first study year. The students have the training at the Ondrejov Observatory (Czech Republic) and at the astronomical station on the mountain Vidojevica in southern Serbia. Astronomy research in Serbia is performed at the Astronomical Observatory, Belgrade and the Department of Astronomy, Faculty of Mathematics, University of Belgrade. There are about 70 researchers in astronomy in Serbia (and about as many abroad) who participate in eight projects financed by the Ministry of Education and Science and in several international cooperations and projects: SREAC, VAMDC, Belissima (recruitment of experienced expatriate researchers), Astromundus (a 2-year joint master program with other four European universities), LSST. One of the goals in near future is twinning between universities in the SEE region and worldwide. The ever-increasing activities of 20 amateur astronomical societies are also given.
Dark Skies Africa: an NOAO and IAU OAD Program on Light Pollution
NASA Astrophysics Data System (ADS)
Walker, Constance E.; Tellez, D.; Pompea, S. M.
The IAU's Office of Astronomy for Development (OAD) awarded the National Optical Astronomy Observatory (NOAO) with a grant to deliver a "Dark Skies Outreach to Sub-Saharan Africa" program to institutions in 12 African countries during 2013. The program helped students identify wasteful and inefficient lighting and provided ways to reduce consumption and to keep energy costs in check. The goal was to inspire students to be responsible stewards in helping their community safeguard one of Africa's natural resources - a dark night sky. Thirteen kits made by the NOAO Education and Public Outreach group were sent to coordinators at university, science center and planetarium-type institutions in 12 African countries and to the IAU OAD. The program's kit included complete instructional guides and supplies for six activities and a project on energy conservation and responsible lighting. The six activities were taught to the coordinators in a series of six Google+ Hangout sessions scheduled from June to mid-November. The coordinators at the institutions in the twelve countries in turn trained local teachers in junior and senior high schools. The Google+ Hangout sessions also included instruction on carrying out evaluations. From the end of November until mid-December students from the different African countries shared final class projects (such as posters or powerpoints) on the program's website. The entire program was designed to help coordinators and educators work with students, parents and the community to identify dark sky resource, lighting and energy issues and to assess their status, efficiency and effectiveness. Participants will take away from the presentation new techniques on using Google+ Hangout sessions to instruct and sustain a community of coordinators and educators through distance learning as well as immersing them (and their students) in Project Based Learning after a scaffolded sequence of activities.
PREFACE: XXXth International Colloquium on Group Theoretical Methods in Physics (ICGTMP) (Group30)
NASA Astrophysics Data System (ADS)
Brackx, Fred; De Schepper, Hennie; Van der Jeugt, Joris
The XXXth International Colloquium on Group Theoretical Methods in Physics (ICGTMP), also known as the Group30 conference, took place in Ghent (Belgium) from Monday 14 to Friday 18 July 2014. The conference was organised by Ghent University (Department of Applied Mathematics, Computer Science and Statistics, and Department of Mathematical Analysis). The website http://www.group30.ugent.be is still available. The ICGTMP is one of the traditional conference series covering the most important topics of symmetry which are relevant to the interplay of present-day mathematics and physics. More than 40 years ago a group of enthusiasts, headed by H. Bacry of Marseille and A. Janner of Nijmegen, initiated a series of annual meetings with the aim to provide a common forum for scientists interested in group theoretical methods. At that time most of the participants belonged to two important communities: on the one hand solid state specialists, elementary particle theorists and phenomenologists, and on the other mathematicians eager to apply newly-discovered group and algebraic structures. The conference series has become a meeting point for scientists working at modelling physical phenomena through mathematical and numerical methods based on geometry and symmetry. It is considered as the oldest one among the conference series devoted to geometry and physics. It has been further broadened and diversified due to the successful applications of geometric and algebraic methods in life sciences and other areas. The first four meetings took place alternatively in Marseille and Nijmegen. Soon after, the conference acquired an international standing, especially following the 1975 colloquium in Nijmegen and the 1976 colloquium in Montreal. Since then it has been organized in many places around the world. It has become a bi-annual colloquium since 1990, the year it was organized in Moscow. This was the first time the colloquium took place in Belgium. There were 246 registered
Large-Scale Sequencing: The Future of Genomic Sciences Colloquium
Margaret Riley; Merry Buckley
Genetic sequencing and the various molecular techniques it has enabled have revolutionized the field of microbiology. Examining and comparing the genetic sequences borne by microbes - including bacteria, archaea, viruses, and microbial eukaryotes - provides researchers insights into the processes microbes carry out, their pathogenic traits, and new ways to use microorganisms in medicine and manufacturing. Until recently, sequencing entire microbial genomes has been laborious and expensive, and the decision to sequence the genome of an organism was made on a case-by-case basis by individual researchers and funding agencies. Now, thanks to new technologies, the cost and effort of sequencing is within reach for even the smallest facilities, and the ability to sequence the genomes of a significant fraction of microbial life may be possible. The availability of numerous microbial genomes will enable unprecedented insights into microbial evolution, function, and physiology. However, the current ad hoc approach to gathering sequence data has resulted in an unbalanced and highly biased sampling of microbial diversity. A well-coordinated, large-scale effort to target the breadth and depth of microbial diversity would result in the greatest impact. The American Academy of Microbiology convened a colloquium to discuss the scientific benefits of engaging in a large-scale, taxonomically-based sequencing project. A group of individuals with expertise in microbiology, genomics, informatics, ecology, and evolution deliberated on the issues inherent in such an effort and generated a set of specific recommendations for how best to proceed. The vast majority of microbes are presently uncultured and, thus, pose significant challenges to such a taxonomically-based approach to sampling genome diversity. However, we have yet to even scratch the surface of the genomic diversity among cultured microbes. A coordinated sequencing effort of cultured organisms is an appropriate place to begin
Report of the IAU Working Group on Cartographic Coordinates and Rotational Elements of the Planets and Satellites
Davies, M.E.; Abalakin, V.K.; Cross, C.A.; Duncombe, R.L.; Masursky, H.; Morando, B.; Owen, T.C.; Seidelmann, P.K.; Sinclair, A.T.; Wilkins, G.A.; Tjuflin, Y.S.
This paper is the entire report of the IAU Working Group on Cartographic Coordinates and Rotational Elements of the Planets and Satellites, including three annexes. Tables give the recemmended values for the directions of the north poles of rotation and the prime meridians of the planets and satellites. Reference surfaces for mapping these bodies are described. The annexes discuss the guiding principles, given in the body of the report, present explanatory notes, and provide a bibliography of the rotational elements and reference surfaces of the planets and satellites, definitions, and algebraic expressions of relevant parameters. ?? 1980 D. Reidel Publishing Co.
Dark Skies Africa: a Prototype Project with the IAU Office of Astronomy for Development
NASA Astrophysics Data System (ADS)
Walker, Constance Elaine; Tellez, Daniel; Pompea, Stephen M.
The IAU's Office of Astronomy for Development (OAD) awarded the National Optical Astronomy Observatory (NOAO) with a grant to deliver a "Dark Skies Outreach to Sub-Saharan Africa" program to institutions in 12 African countries during 2013: Algeria, Nigeria, Rwanda, Tanzania, Ghana, Zambia, South Africa, Ethiopia, Gabon, Kenya, Namibia and Senegal. The program helped students identify wasteful and inefficient lighting and provided ways to reduce consumption and to keep energy costs in check. The goal was to inspire students to be responsible stewards in helping their community safeguard one of Africa's natural resources - a dark night sky.Thirteen kits made by the NOAO Education and Public Outreach group were sent to coordinators at university, science center and planetarium-type institutions in the 12 countries and to the IAU OAD. The program's kit included complete instructional guides and supplies for six hands-on activities (e.g., on the importance of shielding lights and using energy efficient bulbs) and a project on energy conservation and responsible lighting (through energy audits). The activities were taught to the coordinators in a series of six Google+ Hangout sessions scheduled from June to mid-November. The coordinators at the institutions in turn trained local teachers in junior and senior high schools. The Google+ Hangout sessions also included instruction on carrying out evaluations. From the end of November until mid-December students from the different African countries shared final class projects (such as posters or powerpoints) on the program's website.The entire program was designed to help coordinators and educators work with students, parents and the community to identify dark sky resource, lighting and energy issues and to assess their status, efficiency and effectiveness. The audience will take away from the presentation lessons learned on how well the techniques succeeded in using Google+ Hangout sessions to instruct and
Colloquium and Report on Systems Microbiology: Beyond Microbial Genomics
Merry R. Buckley
The American Academy of Microbiology convened a colloquium June 4-6, 2004 to confer about the scientific promise of systems microbiology. Participants discussed the power of applying a systems approach to the study of biology and to microbiology in particular, specifics about current research efforts, technical bottlenecks, requirements for data acquisition and maintenance, educational needs, and communication issues surrounding the field. A number of recommendations were made for removing barriers to progress in systems microbiology and for improving opportunities in education and collaboration. Systems biology, as a concept, is not new, but the recent explosion of genomic sequences and related data has revived interest in the field. Systems microbiology, a subset of systems biology, represents a different approach to investigating biological systems. It attempts to examine the emergent properties of microorganisms that arise from the interplay of genes, proteins, other macromolecules, small molecules, organelles, and the environment. It is these interactions, often nonlinear, that lead to the emergent properties of biological systems that are generally not tractable by traditional approaches. As a complement to the long-standing trend toward reductionism, systems microbiology seeks to treat the organism or community as a whole, integrating fundamental biological knowledge with genomics, metabolomics, and other data to create an integrated picture of how a microbial cell or community operates. Systems microbiology promises not only to shed light on the activities of microbes, but will also provide biology the tools and approaches necessary for achieving a better understanding of life and ecosystems. Microorganisms are ideal candidates for systems biology research because they are relatively easy to manipulate and because they play critical roles in health, environment, agriculture, and energy production. Potential applications of systems microbiology research
Toward Mastery Leadership in Access, Assessment, and Developmental Education: Summary Report of a Colloquium Held in Traverse City, Michigan, July, 1986.
ERIC Educational Resources Information Center
Keyser, John S., Ed.; Floyd, Deborah L., Ed.
In July 1986, a colloquium was convened to develop a position paper on access, assessment, and developmental education. This colloquium report contains the keynote speeches presented at the event, along with a statement developed by the participants regarding the issues. First, introductory material describes the purposes, sponsorship, and group…
University, Government, and the Foreign Graduate Student; A Summary of the Colloquium on the Foreign Graduate Student, Held at Wingspread, Racine, Wisconsin, March 30-31, 1967.
ERIC Educational Resources Information Center
College Entrance Examination Board, New York, NY.
This booklet contains a summary of the colloquium discussion including the major observations and recommendations, and three of the papers that were presented. The colloquium discussion focussed on a number of broad questions in relation to foreign graduate student programs: (1) prospects, assumptions, policies; and responsibilities from the…
Microbial Production of Energy Colloquium- March 10-12, 2006
Merry Buckley; Judy Wall
The American Academy of Microbiology convened a colloquium March 10-12, 2006, in San Francisco, California, to discuss the production of energy fuels by microbial conversions. The status of research into various microbial energy technologies, the advantages and disadvantages of each of these approaches, research needs in the field, and education and training issues were examined, with the goal of identifying routes for producing biofuels that would both decrease the need for fossil fuels and reduce greenhouse gas emissions. Currently, the choices for providing energy are limited. Policy makers and the research community must begin to pursue a broader array of potential energy technologies. A diverse energy portfolio that includes an assortment of microbial energy choices will allow communities and consumers to select the best energy solution for their own particular needs. Funding agencies and governments alike need to prepare for future energy needs by investing both in the microbial energy technologies that work today and in the untested technologies that will serve the world's needs tomorrow. More mature bioprocesses, such as ethanol production from starchy materials and methane from waste digestors, will find applications in the short term. However, innovative techniques for liquid fuel or biohydrogen production are among the longer term possibilities that should also be vigorously explored, starting now. Microorganisms can help meet human energy needs in any of a number of ways. In their most obvious role in energy conversion, microorganisms can generate fuels, including ethanol, hydrogen, methane, lipids, and butanol, which can be burned to produce energy. Alternatively, bacteria can be put to use in microbial fuel cells, where they carry out the direct conversion of biomass into electricity. Microorganisms may also be used some day to make oil and natural gas technologies more efficient by sequestering carbon or by assisting in the recovery of oil and
Report of the IAU Commission 4 Working Group on standardizing access to ephemerides and File format specification
NASA Astrophysics Data System (ADS)
Hilton, J.; Acton, A.; Arlot, J.-E.; Bell, , S. A.; Capitaine, N.; Fienga, A.; Folkner, W. M.; Gastineau, M.; Pavlov, D.; Pitjeva, E. V.; Skripnichenko, V. I.; Wallace, P. T.
The IAU Commission 4 Working Group on Standardizing Access to Ephemerides recommends the use of the Spacecraft and Planet Kernel (SPK) file format to provide a uniform format for the position ephemerides of planets and other natural solar system bodies, and the use of the binary Planetary Constants Kernel (PCK) format for the orientation of a body. It further recommends supporting data be stored in a text PCK. These formats are used by the SPICE system developed by the Jet Propulsion Laboratory. A new data type, Type 20: Chebyshev (Velocity Only) has been added. Other changes to the specification are new object identification numbers for coordinate time ephemerides, and a set of three new data types that uses the TCB rather than the TDB timescale.
Report of the IAU Commission Working Group on Standardizing Access to Ephemerides and File Format Specification: Update September 2014
NASA Astrophysics Data System (ADS)
Hilton, J.; Acton, C.; Arlot, J.-E.; Bell, S.; Capitaine, N.; Fienga, A.; Folkner, W.; Gastineau, M.; Pavlov, D.; Pitjeva, E.; Skripnichenko, V.; Wallace, P.
The IAU Commission 4 Working Group on Standardizing Access to Ephemerides recommends the use of the Spacecraft and Planet Kernel (SPK) file format to provide a uniform format for the position ephemerides of planets and other natural solar system bodies. The Working Group also recommends the use of the binary Planetary Constants Kernel (PCK) format ephemeris file for the orientation of a body. It further recommends supporting data be stored in a text PCK. Since the previous report: - Some minor changes have been made to the formats for the coordinate time ephemeris, data types 20: Chebyshev Polynomials (Velocity Only) and 120: Chebyshev Polynomials (TCB:Velocity Only). - the working group's final report is currently undergoing review by the Navigation and Ancillary Information Facility (NAIF) of NASA's Jet Propulsion Laboratory (JPL) to assure it correctly describes these file formats.
Best Practices for Creating an Observatory or Telescope Bibliography from the IAU Commission 5 Working Group on Libraries
NASA Astrophysics Data System (ADS)
Lagerstrom, J.
Telescope bibliographies have been used for many years to illustrate the scholarly impact of a particular facility. Often, however, the methods used to create these bibliographies were developed independently and not always shared. As a result, it is often difficult to judge the relative impact among facilities. Best Practices for Creating an Observatory or Telescope Bibliography was developed following discussions at the International Astronomical Union's Commission 5 Working Group on Libraries meeting at the 2012 IAU General Assembly in Beijing. This community-driven document identifies the basic components needed to create a bibliography policy that is transparent and the results of which are intended to be reproducible and retrievable by any entity to within a 5% error rate. This paper will review the details of the document as well as its history, progress, and future.
The Sackler Colloquium on promises and perils in nanotechnology for medicine
Austin, Robert H.; Lim, Shuang-fang
The Sackler Colloquium entitled "Nanomaterials in Biology and Medicine: Promises and Perils" was held on April 10–11, 2007. We have been able to assemble a representative sampling of 17 of the invited talks ranging over the topics presented. Any new technology carries with it both a promise of transforming the way we do things and the possibility that there are unforeseen consequences. The papers collected here represent a cross-section of these issues. As an example, we present our own work on nano-upconversion phosphors as an example of this new class of nanomaterials with potential use in medicine and biology. PMID:18981427
The Sackler Colloquium on promises and perils in nanotechnology for medicine.
Austin, Robert H; Lim, Shuang-fang
The Sackler Colloquium entitled "Nanomaterials in Biology and Medicine: Promises and Perils" was held on April 10-11, 2007. We have been able to assemble a representative sampling of 17 of the invited talks ranging over the topics presented. Any new technology carries with it both a promise of transforming the way we do things and the possibility that there are unforeseen consequences. The papers collected here represent a cross-section of these issues. As an example, we present our own work on nano-upconversion phosphors as an example of this new class of nanomaterials with potential use in medicine and biology. PMID:18981427
Supervision and the Teacher: The Odd Couple. Papers Presented at the New York State Association of Foreign Language Teachers Colloquium.
ERIC Educational Resources Information Center
Born, Warren C., Ed.
This compilation of papers presented at the New York State Association of Foreign Language Teachers Colloquium focuses on the interrelated roles of the foreign language teacher and the language program supervisor. The following papers are included: (1) "The Foreign Language Curriculum: A Joint Venture" by Charles Blake; (2) "Updated Observation…
Higher Education in Federal Systems. Proceedings of an International Colloquium (Queen's University, Kingston, Ontario, Canada, May 8-10, 1991).
ERIC Educational Resources Information Center
Brown, Douglas, Ed.; And Others
This volume contains the proceedings of an international colloquium on higher education in federal countries with complex divisions of responsibility for the many facets of higher education. The volume is organized in four parts. Part I contains one paper, "The Federal Context for Higher Education" by Ronald L. Watts and a description of the…
Proceeding of the International Scientific Colloquium: MATHEMATICS AND CHILDREN (How to Teach and Learn Mathematics) (Osijek, Croatia, April 13, 2007)
ERIC Educational Resources Information Center
Pavlekovic, Margita, Ed.
The main aim of the Organisational Committee of the international scientific colloquium Mathematics and Children is to encourage additional scientific research in the field of mathematics teaching in Croatia. The development of science and education is a part of a long-term Education Sector Development Plan 2005-2010. Following the example of…
College Scholarship Service Colloquium on Student Loan Counseling & Debt Management. Proceedings (Denver, Colorado, December 2-4, 1985).
ERIC Educational Resources Information Center
College Entrance Examination Board, New York, NY. Coll. Scholarship Service.
Student loan counseling and debt management are discussed in three papers, six commentaries, and a panel discussion from a College Scholarship Service colloquium. In "Fulfilling the Institution's Responsibilities to Student Borrowers," Theodore J. Marchese discusses a shift in student financial aid marked by the ascendency of loans instead of…
Colombo Plan Intra-Regional Technician Training Colloquium (6th, Kuala Lumpur, Malaysia, April 21-25, 1975).
ERIC Educational Resources Information Center
Colombo Plan Bureau (Sri Lanka).
Proceedings of the Sixth Colloquium on Intra-Regional Technical Training sponsored jointly by the Colombo Plan and the Government of Malaysia are presented in this report. Four working papers are presented centered around three main areas of concern: influence of technical education on economic development; how the status of technicians could be…
Official Languages and the Economy. New Canadian Perspectives. Papers Presented at a Colloquium (Ottawa, Ontario, Canada, May 5, 1995).
ERIC Educational Resources Information Center
Canadian Heritage, Ottawa (Ontario).
Papers from a colloquium on the relationship between Canada's official languages and its economy include: "Economic Dimensions of Minority and Foreign Language Use: An International Overview" (Karim H. Karim); "European Research on the economics of Language: Recent Results and Relevance to Canada" (Francois Grin); "Reflections on Some Economic…
Scientist to scientist colloquium steering committee planning session. Summary report of the proceedings
The reason for holding a scientific colloquium of this nature is to bring together the most active scientific researchers for cross-disciplinary exchanges. As one scientist commented, it is a way to compensate for over-specialization. As a scientist/administrator noted, it helps administrators to have access to high-level scientific information in a setting where they can ask stupid questions. At a meeting of between 80 and 100 people small group exchanges are possible, allowing more in-depth discussion. In five days of meetings, there are many opportunities for a great number of these exchanges. The Keystone Process facilitates intermingling across disciplines and encourages debate. Because this meeting is unlike discipline-specific meetings, presenters must write a talk specifically for an interdisciplinary audience, touching on various scientific and social implications of their work. They use this opportunity to practice addressing a broad audience which includes their peers from other /fields, university administrators, industry executives, government officials, and members of the media who will help bring forefront scientific findings to the public. This report discusses purpose, funding, and outcome of the colloquium.
Synopsis of the 6th Walker's Cay Colloquium on Cancer Vaccines and Immunotherapy
Kast, W Martin; Levitsky, Hyam; Marincola, Francesco M
The 6th annual Cancer Vaccines and Immunotherapy Colloquium at Walker's Cay was held under the auspices of the Albert B. Sabin Vaccine Institute on March 10–13, 2004. The Colloquium consisted of a select group of 34 scientists representing academia, biotechnology and pharmaceutical industry. The main goal of this gathering was to promote in a peaceful and comfortable environment exchanges between basic and clinical science. The secondary benefit was to inspire novel bench to bedside ventures and at the same time provide feed back about promising and/or disappointing clinical results that could help re-frame some scientific question or guide the design of future trials. Several topics were covered that included tumor antigen discovery and validation, platforms for vaccine development, tolerance, immune suppression and tumor escape mechanisms, adoptive T cell therapy and dendritic cell-based therapies, clinical trials and assessment of response. Here we report salient points raised by speakers or by the audience during animated discussion that followed each individual presentation. PMID:15212694
Appendix: Final Update of the IAU Division A Commission 4 Working Group on Standardizing Access to Ephemerides and File Format Specification
NASA Astrophysics Data System (ADS)
Hilton, James L.; Acton, Charles; Arlot, Jean-Eudes; Bell, Steven A.; Capitaine, Nicole; Fienga, Agnès; Folkner, William M.; Gastineau, Mickaël; Pavlov, Dmitry; Pitjeva, Elena V.; Skripnichenko, Vladimir I.; Wallace, Patrick
The IAU Commission 4 Working Group on Standardizing Access to Ephemerides recommends the use of the Spacecraft and Planet Kernel (SPK) format to provide a uniform format for the position ephemerides of planets and other natural solar system bodies, and the use of the Planetary Constants Kernel (PCK) for the orientation of these bodies. These formats are used by the SPICE system, developed by the Navigation and Ancillary Information Facility of NASA's Jet Propulsion Laboratory. The working group's final report is currently undergoing final preparations for publication. A long version of this report will be available at the IAU Commission 4: Ephemerides (or its successor) web site. This long version will contain a full description of that portion of the SPK and PCK formats required to duplicate these file types for this application.
Astronomy for a Better World: IAU OAD Task Force-1 Programs for Advancing Astronomy Education and Research in Universities in Developing Countries
NASA Astrophysics Data System (ADS)
Guinan, Edward; Kolenberg, Katrien
We discuss the IAU Commission 46 and Office for Astronomy Development (OAD) programs that support advancing Astronomy education and research primarily in universities in developing countries. The bulk of these operational activities will be coordinated through the OAD's newly installed Task Force 1. We outline current (and future) IAU/OAD Task Force-1 programs that promote the development of University-level Astronomy at both undergraduate and graduate levels. Among current programs discussed are the past and future expanded activities of the International School for Young Astronomers (ISYA) and the Teaching Astronomy for Development (TAD) programs. The primary role of the ISYA program is the organization of a three week School for students for typically M.Sc. and Ph.D students. The ISYA is a very successful program that will now be offered more frequently through the generous support of the Kavli Foundation. The IAU/TAD program provides aid and resources for the development of teaching, education and research in Astronomy. The TAD program is dedicated to assist countries that have little or no astronomical activity, but that wish to develop or enhance Astronomy education. Over the last ten years, the ISYA and TAD programs have supported programs in Africa, Asia, Central America and the Caribbean, the Middle East, South East and West Asia, and South America. Several examples are given. Several new programs being considered by OAD Task Force-1 are also discussed. Other possible programs being considered are the introduction of modular Astronomy courses into the university curricula (or improve present courses) as well as providing access to ``remote learning`` courses and Virtual Astronomy labs in developing countries. Another possible new program would support visits of astronomers from technically advanced countries to spend their sabbatical leaves teaching and advising University Astronomy programs in developing countries. Suggestions for new Task Force -1
PREFACE: XXXth International Colloquium on Group Theoretical Methods in Physics (ICGTMP) (Group30)
NASA Astrophysics Data System (ADS)
Brackx, Fred; De Schepper, Hennie; Van der Jeugt, Joris
The XXXth International Colloquium on Group Theoretical Methods in Physics (ICGTMP), also known as the Group30 conference, took place in Ghent (Belgium) from Monday 14 to Friday 18 July 2014. The conference was organised by Ghent University (Department of Applied Mathematics, Computer Science and Statistics, and Department of Mathematical Analysis). The website http://www.group30.ugent.be is still available. The ICGTMP is one of the traditional conference series covering the most important topics of symmetry which are relevant to the interplay of present-day mathematics and physics. More than 40 years ago a group of enthusiasts, headed by H. Bacry of Marseille and A. Janner of Nijmegen, initiated a series of annual meetings with the aim to provide a common forum for scientists interested in group theoretical methods. At that time most of the participants belonged to two important communities: on the one hand solid state specialists, elementary particle theorists and phenomenologists, and on the other mathematicians eager to apply newly-discovered group and algebraic structures. The conference series has become a meeting point for scientists working at modelling physical phenomena through mathematical and numerical methods based on geometry and symmetry. It is considered as the oldest one among the conference series devoted to geometry and physics. It has been further broadened and diversified due to the successful applications of geometric and algebraic methods in life sciences and other areas. The first four meetings took place alternatively in Marseille and Nijmegen. Soon after, the conference acquired an international standing, especially following the 1975 colloquium in Nijmegen and the 1976 colloquium in Montreal. Since then it has been organized in many places around the world. It has become a bi-annual colloquium since 1990, the year it was organized in Moscow. This was the first time the colloquium took place in Belgium. There were 246 registered
Federal science funding priorities, anti-terrorism debated at AAAS Colloquium
NASA Astrophysics Data System (ADS)
Showstack, Randy
John Marburger, director of the White House Office of Science and Technology Policy has said that some federal science agencies not slated to receive big increases in the administration's proposed fiscal year 2003 budget could do better in upcoming years.In remarks on 11 April at a colloquium on science and technology policy, Marburger defended the Bush administration's push for increasing research funding for the National Institutes of Health (NIH) and other administration priorities, and he cautioned that tough budget decisions have to be made in light of the current tight economic climate and the large number of potential scientific opportunities. But he also said that funding levels for some agencies and science areas could increase at a later date during the administration's tenure.
Reshaped destinies: confronting our human future the need for and promise of an interdisciplinary colloquium.
Solomon, Louis M; Noll, Rebekka C
The genomic revolution is bringing with it simultaneous needs for both scientists and nonscientists to understand and assess, in an unvarnished and nonjudgmental way, the implications of genometry. This is the field of science and technology that is taking the genetic code and what we have learned from its secrets, and reshaping our individual and collective human destinies. Together with the editor-in-chief of Gender Medicine, the authors propose an interdisciplinary group-populated by those in science, law, ethics, social policy, and the interested public-to observe, understand, and disseminate information about what is occurring in the fields of biology and chemistry that is the driving force of the genomic revolution. This article discusses the background to the Redefined Destinies Colloquium (RDC) and summarizes 4 of the topics the RDC is studying. PMID:19108807
Colloquium: The Einstein-Podolsky-Rosen paradox: From concepts to applications
Reid, M. D.; Drummond, P. D.; Bowen, W. P.; Cavalcanti, E. G.; Lam, P. K.; Bachor, H. A.; Andersen, U. L.; Leuchs, G.
This Colloquium examines the field of the Einstein, Podolsky, and Rosen (EPR) gedanken experiment, from the original paper of Einstein, Podolsky, and Rosen, through to modern theoretical proposals of how to realize both the continuous-variable and discrete versions of the EPR paradox. The relationship with entanglement and Bell's theorem are analyzed, and the progress to date towards experimental confirmation of the EPR paradox is summarized, with a detailed treatment of the continuous-variable paradox in laser-based experiments. Practical techniques covered include continuous-wave parametric amplifier and optical fiber quantum soliton experiments. Current proposals for extending EPR experiments to massive-particle systems are discussed, including spin squeezing, atomic position entanglement, and quadrature entanglement in ultracold atoms. Finally, applications of this technology to quantum key distribution, quantum teleportation, and entanglement swapping are examined.
Cellular Interactions and Signaling in NeuroAIDS: Emerging Issues Colloquium
Al-Harthi, Lena; Buch, Shilpa; Geiger, Jonathan D.; Gendelman, Howard E.; He, Johnny; Jordan-Sciutto, Kelly L.; Kolson, Dennis L.; Rappaport, Jay; Roy, Sabita; Zheng, Jialin; Fox, Howard S.
On May 23, 2013 scientific leaders in the neuroAIDS community met at the University of Nebraska Medical Center to discuss cellular interaction and signaling for the third annual human immunodeficiency virus and neuroAIDS colloquium. The meeting continues a series of contemporary scientific issues related to how virus effects the nervous system. In 2011 the focus was on animal models and in 2012 in biomarkers. Here, our 2013 meeting featured ten presentations from outstanding scientists examining how inter- and intra-cellular processes contribute to neuropathogenesis. Talks highlighted emerging issues, findings, and potential therapies, followed by a panel discussion in which controversies in the field and gaps in our current knowledge were identified. The panel discussion was transcribed into the article and published as a field perspective. A link is available where all of the presentations and the concluding discussion can be seen and heard. PMID:24789373
Oklo and the Speed of Light at SLAC's Next Colloquium!
Dr. Steve Lamoreaux
Natural nuclear reactors? Changes in the speed of light? If either of these concepts seem implausible to you now they certainly won't once Dr. Steve Lamoreaux (LANL) delivers his SLAC Colloquium lecture in the Panofsky Auditorium on November 7th at 4:15 pm entitled The Oklo Natural Reactor and the Time Variability of the Fundamental Constants of Nature. This lecture is a rare opportunity to learn not only about Oklo's incredible natural nuclear reactors but also to gain understanding about how the present-day study of these sites may alter our understanding of fundamental constants such as the speed of light. This event is a must-see for the curious!
Proceedings of the 127th Colloquium of the International Astronomical Union Reference Systems
NASA Astrophysics Data System (ADS)
Hughes, James A.; Smith, Clayton A.; Kaplan, George H.
Both invited oral and poster papers were presented on topics ranging from theoretical relativistic considerations to new observational programs and results. Partial contents include a report of the Subgroup on Time; preliminary report of the work of the Subgroup on Coordinate Frames and Origins; activity report of the IAU Working Group on reference system: subgroup on astronomical constants; relativistic hierarchy of reference systems and time scales; relativistic celestial mechanics and reference frames; current status of the astrometric capabilities of the Hubble Space Telescope fine guidance sensors; necessary procedures to reach an agreeable reference frame: counterproposal to the circular letter no. 4 of Kovalevsky; stability of the extragalactic reference frame realized by VLBI; The ZMOA-1990 nutation series; and long-period perturbations in terrestrial reference frames.
MayDay Colloquium 23: The End(s) of Music Education? A Call for Re-Visioning
ERIC Educational Resources Information Center
Bates, Vincent C.
In the summer of 2011 (June 16-19), the MayDay Group met in Salt Lake City, Utah (USA) for MayDay Colloquium 23, with presentations and discussions on the theme,"The End(s) of Music Education? A Call for Re-Visioning": In a time of rapidly changing political processes, power relations, and policies, music educators are challenged to…
EDITORIAL: Precision Measurement Technology at the 56th International Scientific Colloquium in Ilmenau Precision Measurement Technology at the 56th International Scientific Colloquium in Ilmenau
NASA Astrophysics Data System (ADS)
Manske, E.; Froehlich, T.
The 56th International Scientific Colloquium was held from 12th to 16th September 2011 at the Ilmenau University of Technology in Germany. This event was organized by the Faculty of Mechanical Engineering under the title: 'Innovation in Mechanical Engineering—Shaping the Future' and was intended to reflect the entire scope of modern mechanical engineering. In three main topics many research areas, all involving innovative mechanical engineering, were addressed, especially in the fields of Precision Engineering and Precision Measurement Technology, Mechatronics and Ambient-Assisted Living and Systems Technology. The participants were scientists from 21 countries, and 166 presentations were given. This special issue of Measurement Science and Technology presents selected contributions on 'Precision Engineering and Precision Measurement Technology'. Over three days the conference participants discussed novel scientific results in two sessions. The main topics of these sessions were: Measurement and Sensor Technology Process measurement Laser measurement Force measurement Weighing technology Temperature measurement Measurement dynamics and Nanopositioning and Nanomeasuring Technology Nanopositioning and nanomeasuring machines Nanometrology Probes and tools Mechanical design Signal processing Control and visualization in NPM devices Significant research results from the Collaborative Research Centre SFB 622 'Nanopositioning and Nanomeasuring Machines' funded by the German Research Foundation (DFG) were presented as part of this topic. As the Chairmen, our special thanks are due to the International Programme Committee, the Organization Committee and the conference speakers as well as colleagues from the Institute of Process Measurement and Sensor Technology who helped make the conference a success. We would like to thank all the authors for their contributions, the referees for their time spent reviewing the contributions and their valuable comments, and the whole
NASA Astrophysics Data System (ADS)
Amoroso, Richard L.
HÉCTOR A.A brief introductory survey of Unified Field Mechanics (UFM) is given from the perspective of a Holographic Anthropic Multiverse cosmology in 12 `continuous-state' dimensions. The paradigm with many new parameters is cast in a scale-invariant conformal covariant Dirac polarized vacuum utilizing extended HD forms of the de Broglie-Bohm and Cramer interpretations of quantum theory. The model utilizes a unique form of M-Theory based in part on the original hadronic form of string theory that had a variable string tension, TS and included a tachyon. The model is experimentally testable, thus putatively able to demonstrate the existence of large-scale additional dimensionality (LSXD), test for QED violating tight-bound state spectral lines in hydrogen `below' the lowest Bohr orbit, and surmount the quantum uncertainty principle utilizing a hyperincursive Sagnac Effect resonance hierarchy.
NASA Astrophysics Data System (ADS)
Gratton, Raffaele G.
The assembly of the halo yields fundamental information on the formation and evolution of galaxies: this was quite exhaustively discussed at this very important symposium. I present a brief personal summary of the meeting, outlining those points that I found more exciting and suggestive. I also remarked a few areas that were possibly not enough expanded. I found this research field extremely interesting and I think there are great expectations for new developments in the next few years, thanks to the new large spectroscopic surveys and the ESA GAIA satellite.
Colloquium: Time-reversal violation with quantum-entangled B mesons
NASA Astrophysics Data System (ADS)
Bernabéu, J.; Martínez-Vidal, F.
Symmetry transformations have been proven a bedrock tool for understanding the nature of particle interactions, formulating, and testing fundamental theories. Based on the up to now unbroken C P T symmetry, the violation of the C P symmetry between matter and antimatter by weak interactions, discovered in the decay of kaons in 1964 and observed more recently in 2001 in B mesons, strongly suggests that the behavior of these particles under weak interactions must also be asymmetric under time reversal T . However, until recent years there has not been a direct detection of the expected time-reversal violation in the time evolution of any system. This Colloquium examines the field of time-reversal symmetry breaking in the fundamental laws of physics. For transitions, its observation requires an asymmetry with exchange of initial and final states. A discussion is given of the conceptual basis for such an exchange with unstable particles, using the quantum properties of Einstein-Podolsky-Rosen entanglement available at B meson factories combined with the decay as a filtering measurement. The method allows a clear-cut separation of different transitions between flavor and C P eigenstates in the decay of neutral B mesons. These ideas have been implemented for the experiment by the BABAR Collaboration at SLAC's B factory. The results, presented in 2012, prove beyond any doubt the violation of time-reversal invariance in the time evolution between these two states of the neutral B meson.
Summary Report on the Transportation Combustion Engine Efficiency Colloquium Held at USCAR, March 3 and 4, 2010
Daw, C Stuart; Graves, Ronald L; Caton, Jerald A; Wagner, Robert M
This report summarizes results from an invited two-day colloquium of twenty-nine combustion engine experts from academia, industry, and national labs that was convened March 3rd and 4th, 2010, at the headquarters of the United States Council for Automotive Research (USCAR) in Southfield, Michigan. The colloquium was held at the request of The Department of Energy (DOE) Office of Freedom Car and Vehicle Technologies (OFCVT) to review and assess the current state of transportation combustion engine technology from theoretical and practical perspectives. In the ensuing discussions, the experts were able to reach a broad consensus on some important questions regarding current fuel efficiency limits. They also identified technology barriers and recommended specific near and longer-term R&D priorities for DOE's consideration. Internal combustion engines currently play a dominant role in U.S. transportation and are expected to continue to do so well beyond 2020 [1]. Because of this, the Department of Energy (DOE) has placed high priority on promoting technologies that maximize combustion engine fuel efficiency while minimizing greenhouse gas emissions. Identification of the most promising paths to achieve these goals has recently become more complicated as non-traditional transportation fuels and hybrid electric vehicles become widely available. To reassess the state of combustion engine science and identify new opportunities for technology breakthroughs, an invited colloquium of combustion engine experts was convened on March 3rd and 4th, 2010, at the headquarters of the United States Council for Automotive Research (USCAR) in Southfield, Michigan. The colloquium objectives were: (1) Review and assess the current state of transportation combustion engine technology from both theoretical and practical perspectives; (2) Arrive at a consensus on the theoretical and practical fuel efficiencies that can be achieved; and (3) Recommend near and longer-term R&D priorities for
Colloquium: Majorana fermions in nuclear, particle, and solid-state physics
NASA Astrophysics Data System (ADS)
Elliott, Steven R.; Franz, Marcel
Ettore Majorana (1906-1938) disappeared while traveling by ship from Palermo to Naples in 1938. His fate has never been fully resolved and several articles have been written that explore the mystery itself. His demise intrigues us still today because of his seminal work, published the previous year, that established symmetric solutions to the Dirac equation that describe a fermionic particle that is its own antiparticle. This work has long had a significant impact in neutrino physics, where this fundamental question regarding the particle remains unanswered. But the formalism he developed has found many uses as there are now a number of candidate spin-1 /2 neutral particles that may be truly neutral with no quantum number to distinguish them from their antiparticles. If such particles exist, they will influence many areas of nuclear and particle physics. Most notably the process of neutrinoless double beta decay can exist only if neutrinos are massive Majorana particles. Hence, many efforts to search for this process are underway. Majorana's influence does not stop with particle physics, however, even though that was his original consideration. The equations he derived also arise in solid-state physics where they describe electronic states in materials with superconducting order. Of special interest here is the class of solutions of the Majorana equation in one and two spatial dimensions at exactly zero energy. These Majorana zero modes are endowed with some remarkable physical properties that may lead to advances in quantum computing and, in fact, there is evidence that they have been experimentally observed. This Colloquium first summarizes the basics of Majorana's theory and its implications. It then provides an overview of the rich experimental programs trying to find a fermion that is its own antiparticle in nuclear, particle, and solid-state physics.
Colloquium: Biophysical principles of undulatory self-propulsion in granular media
NASA Astrophysics Data System (ADS)
Goldman, Daniel I.
Biological locomotion, movement within environments through self-deformation, encompasses a range of time and length scales in an organism. These include the electrophysiology of the nervous system, the dynamics of muscle activation, the mechanics of the skeletal system, and the interaction mechanics of such structures within natural environments like water, air, sand, and mud. Unlike the many studies of cellular and molecular scale biophysical processes, movement of entire organisms (like flies, lizards, and snakes) is less explored. Further, while movement in fluids like air and water is also well studied, little is known in detail of the mechanics that organisms use to move on and within flowable terrestrial materials such as granular media, ensembles of small particles that collectively display solid, fluid, and gaslike behaviors. This Colloquium reviews recent progress to understand principles of biomechanics and granular physics responsible for locomotion of the sandfish, a small desert-dwelling lizard that "swims" within sand using undulation of its body. Kinematic and muscle activity measurements of sand swimming using high speed x-ray imaging and electromyography are discussed. This locomotion problem poses an interesting challenge: namely, that equations that govern the interaction of the lizard with its environment do not yet exist. Therefore, complementary modeling approaches are also described: resistive force theory for granular media, multiparticle simulation modeling, and robotic physical modeling. The models reproduce biomechanical and neuromechanical aspects of sand swimming and give insight into how effective locomotion arises from the coupling of the body movement and flow of the granular medium. The argument is given that biophysical study of movement provides exciting opportunities to investigate emergent aspects of living systems that might not depend sensitively on biological details.
Colloquium: Multimessenger astronomy with gravitational waves and high-energy neutrinos
NASA Astrophysics Data System (ADS)
Ando, Shin'ichiro; Baret, Bruny; Bartos, Imre; Bouhou, Boutayeb; Chassande-Mottin, Eric; Corsi, Alessandra; Di Palma, Irene; Dietz, Alexander; Donzaud, Corinne; Eichler, David; Finley, Chad; Guetta, Dafne; Halzen, Francis; Jones, Gareth; Kandhasamy, Shivaraj; Kotake, Kei; Kouchner, Antoine; Mandic, Vuk; Márka, Szabolcs; Márka, Zsuzsa; Moscoso, Luciano; Papa, Maria Alessandra; Piran, Tsvi; Pradier, Thierry; Romero, Gustavo E.; Sutton, Patrick; Thrane, Eric; Van Elewyck, Véronique; Waxman, Eli
Many of the astrophysical sources and violent phenomena observed in our Universe are potential emitters of gravitational waves and high-energy cosmic radiation, including photons, hadrons, and presumably also neutrinos. Both gravitational waves (GW) and high-energy neutrinos (HEN) are cosmic messengers that may escape much denser media than photons. They travel unaffected over cosmological distances, carrying information from the inner regions of the astrophysical engines from which they are emitted (and from which photons and charged cosmic rays cannot reach us). For the same reasons, such messengers could also reveal new, hidden sources that have not been observed by conventional photon-based astronomy. Coincident observation of GWs and HENs may thus play a critical role in multimessenger astronomy. This is particularly true at the present time owing to the advent of a new generation of dedicated detectors: the neutrino telescopes IceCube at the South Pole and ANTARES in the Mediterranean Sea, as well as the GW interferometers Virgo in Italy and LIGO in the United States. Starting from 2007, several periods of concomitant data taking involving these detectors have been conducted. More joint data sets are expected with the next generation of advanced detectors that are to be operational by 2015, with other detectors, such as KAGRA in Japan, joining in the future. Combining information from these independent detectors can provide original ways of constraining the physical processes driving the sources and also help confirm the astrophysical origin of a GW or HEN signal in case of coincident observation. Given the complexity of the instruments, a successful joint analysis of this combined GW and HEN observational data set will be possible only if the expertise and knowledge of the data is shared between the two communities. This Colloquium aims at providing an overview of both theoretical and experimental state of the art and perspectives for GW and HEN
Costa Rica Variable Star Observation Program: Continuation of the research started in the Second Astronomical Observation Regional Campaign TAD/IAU Tegucigalpa Honduras, 1998.
NASA Astrophysics Data System (ADS)
Araya Rodriguez, E.
In the last months of January and February, it was the Second Astronomical Observation Regional Campaign TAD/IAU in the Suyapa Astronomical Observatory, Tegucigalpa, Honduras; sponsored by the International Astronomical Union, Honduras Government and the Universidad Nacional Autonoma de Honduras. In that opportunity, during the campaign, it began a variable star observation program, according to international regulation of the American Association of Variable Stars Observers (AAVSO). The activities were about the use of general experimental techniques that allow people to do studies naked eye, with telescopes or photometers depending on the observed star magnitude. The continuation in Costa Rica of that research added to some gotten results will be presented in this work.
Food, Hunger, and Agricultural Issues. Proceedings of a Colloquium on Future U.S. Development Assistance (Morrilton, Arkansas, February 17-19, 1988). Development Education Series.
ERIC Educational Resources Information Center
Clubb, Deborah, Ed.; Ligon, Polly C., Ed.
Colloquium participants were asked to make informed guesses about whether developing countries can grow and equitably distribute the food they need over the next decade, what the international development community should do to help in both production and distribution, and what role the United States should play in the development process. The 17…
This dedicated issue of the Journal of the Air & Waste Management Association contains 17 peer-reviewed scientific papers that were presented at the specialty conference, "Particulate Matter: Atmospheric Sciences, Exposure and the Fourth Colloquium on PM and Human Health," that w...
A Colloquium Review of Pirates of the Cell: The Story of Viruses from Molecule to Microbe, with Selected Readings from Popular Periodicals and Research Journals.
ERIC Educational Resources Information Center
Hagerstown Junior Coll., MD.
This colloquium book review (occasioned by Andrew Scott's "Pirates of the Cell") contains seven selected readings from popular periodicals and research journals. It is designed to eliminate some of the mental barriers that many have to topics like molecular biology and virology. Included are: (1) "What Is A Virus?" (William D. Elliot); (2) "The…
Actes du colloque sur le bilinguisme, Universite de Neuchatel, 14/15 Septembre, 1981 (Proceedings of the Colloquium on Bilingualism, University of Neuchatel, September 14-15, 1981).
ERIC Educational Resources Information Center
This issue contains proceedings of a colloquium on linguistics at the University of Neuchatel: (1) "Propositions epistemologiques pour une etude du bilinguisme (Epistemological Propositions for a Study of Bilingualism)," by B. Py; (2) "Comment on di ca? Prolegomenes a une etude de la composante semantique du langage des migrants (How Do You Say…
Invited Colloquium--on Publishing in Applied Linguistics: A Forum on Innovation and Challenges in a Changing World, AAAL Conference 2014
ERIC Educational Resources Information Center
Byrnes, Heidi
Under the leadership of then 1st vice president and program chair Aneta Pavlenko, Temple University, the 2014 AAAL conference had as one of its focal areas the changing scene of publishing in a digital and global age. Within an array of offerings addressing the theme, this three-hour invited colloquium, organized by Heidi Byrnes, Georgetown…
Construct Validity in Psychological Measurement; Proceedings of a Colloquium on Theory and Application in Education and Employment (Henry Chauncey Conference Center, Princeton, New Jersey, October 1979).
ERIC Educational Resources Information Center
Office of Personnel Management, Washington, DC.
The stimulus for this colloquium was the convergence of several significant developments bearing on the construct validation of standardized tests and other assessment methods. Of these developments, some were fundamental to psychology as a science; others reflected socio-political pressures on measurement in education and employment. The ten…
The International Scientific Colloquium MATHEMATICS AND CHILDREN (The Math Teacher) = Treci medunarodni znanstveni skup MATEMATIKA I DIJETE (Ucitelj matematike) (3rd, Osijek, Croatia, March 18, 2011)
ERIC Educational Resources Information Center
Pavlekovic, Margita, Ed.
In the monograph The Math Teacher (following the Third International Scientific Colloquium Mathematics and Children in 2011), the term "teacher" designates a person who teaches mathematics, and the context of each article reveals whether this implies the teacher at a pre-school institution, a school or a university instructor. In Croatia, much…
Actes des journees de linguistique: Colloque sur la recherche etudiante (Proceedings of the Linguistics Conference: Colloquium on Student Research) (Quebec, Canada, March 18-19, 1988).
ERIC Educational Resources Information Center
Lepage, Danielle, Ed.; Dominik, Annette, Ed.
Presentations by students at a colloquium on student research on the occasion of the 50th anniversary of the University of Laval's Faculty of Letters, March 18-19, 1988, include: "Une enquete sur la qualite du francais ecrit au Quebec"; "Amenagement linguistique et neologie"; "Analyse syntaxique des 'arrets et retours' en arabe morocain parle";…
Teaching the Teachers on Building Climatology. (CIB Steering Group S 4, Colloquium, Stockholm, September 4-6, 1972). CIB Proceedings No. 25.
ERIC Educational Resources Information Center
National Swedish Inst. for Building Research, Stockholm.
This publication comprises a collection of papers and synopses of discussions dating from the "Teaching the Teachers in Building Climatology" colloquium which was held under the auspices of the International Council for Building Research (CIB) and the World Meteorological Organization (WMO). The papers deal with the use of various meteorological…
The satellites of Jupiter; Proceedings of the Fifty-seventh Colloquium, Kailua, Hawaii, May 13-16, 1980
NASA Technical Reports Server (NTRS)
Burns, J. A.
Among the topics covered by the colloquium on the satellites of Jupiter are: the internal energy and thermophysics of the surface of Io, plume volcanism on Io, the photometric variability of Io, the near-surface flow of volcanic gases on Io, and the sodium emission cloud of Io and its north-south asymmetry. Also considered are: the physical processes and origins of Jupiter's ring and its possible effect on the Jovian inner plasmasphere, the composition of such moons of Jupiter as Amalthea, Ganymede, Europa and Callisto and their lithospheric and ice evolutions. Particular attention is given such topographic features as the domes and grooved terrain on Ganymede, water frost and ice, and the photometric properties of these outer satellites of Jupiter.
"Astronomy for a Better World": IAU/OAD Task Force One Activities to Develop Astronomy Education and Research at Universities in the Developing World
NASA Astrophysics Data System (ADS)
Guinan, Edward Francis; Kolenberg, Katrien
The Task Force (1) on Astronomy for Universities & Research (TF-1) was established in 2012 as part of the IAU Office of Astronomy for Development (OAD). This Task Force drives activities related to astronomy education and research at universities mainly in the developing world. Astronomy is used to stimulate research and education in STEM fields and to develop and promote astronomy in regions of the world where there is little or no astronomy. There is also potential for developing research in the historical and cultural aspects of astronomy which may prove important for stimulating an interest in the subject in communities where there is yet no established interest in the science.Since the establishment of the OAD, over 25 TF-1 programs have been funded (or partially funded) to support a wide variety of interesting and innovative astronomy programs in Africa, Asia, South-East Asia, Middle-East, and in South & Central America. Nearly every aspect of development has been supported. These programs include supporting: regional astronomy training schools, specialized workshops, research visits, university twinning programs, distance learning projects, university astronomy curriculum development, as well as small telescope and equipment grants. In addition, a large new program - Astrolab - was introduced (by J-P De Greve and Michele Gerbaldi) to bring starlight" into the class room. In the Astrolab program students carry out and reduce CCD photometry secured by them using remotely controlled telescopes. Results from pilot programs will be discussed.OAD TF-1 programs will be discussed along with future plans for improving and expanding these programs to bring astronomy education and research to a greater number of people and indeed to use Astronomy for a Better World. Information and advice will also be provided about applying for support in the future.
Educational interventions to improve antibiotic use in the community: report from the International Forum on Antibiotic Resistance (IFAR) colloquium, 2002.
Finch, Roger G; Metlay, Joshua P; Davey, Peter G; Baker, Lee J
National and international strategies for the control of antibiotic resistance recommend education for health-care professionals and the public to promote prudent antibiotic use. This paper, based on discussions at the 2002 colloquium of the International Forum on Antibiotic Resistance (IFAR), provides an international discourse between theoretical approaches to behaviour change and practical experience gained in large-scale antibiotic use educational campaigns. Interventions are more likely to be effective if their aim is to change behaviour, rather than provide information. They should target all relevant groups, especially parents, children, day-care staff, and health-care professionals. They should use clear and consistent messages concerning bacterial versus viral infection, prudent antibiotic use, symptomatic treatment, and infection-control measures (eg, handwashing). Campaigns should use a range of communications using pilot-testing, strong branding, and sociocultural adaptation. Prime-time television is likely to be the most effective public medium, while academic detailing is especially useful for health-care professionals. Multifaceted interventions can improve antibiotic prescribing to some degree. However, there are few data on their effects on resistance patterns and patient outcomes, and on their cost-effectiveness. Current research aims include the application of behaviour-change models, the development and validation of prudent antibiotic prescribing standards, and the refinement of tools to assess educational interventions. PMID:14720568
On the research progress of Descartes-Subproject: "Advances in the integration of the equations of the Earth's rotation in the framework of the new parameters adopted by the IAU 2000 Resolutions"
NASA Astrophysics Data System (ADS)
Folgueira, M.; Capitaine, N.; Souchay, J.
This paper reports on the progress of the research European DESCARTES-Subproject entitled: ''Advances in the integration of the equations of the Earth's rotation in the framework of the new parameters adopted by the IAU 2000 Resolutions", describing the scientific approach, the aims and objectives of the work and its successive steps. Firstly, we give a brief overview of the role of the variables in the description of the rotational dynamics of the Earth. Then, we summarize the different mathematical methods used to carry out our investigations, which include analytical, semi-analytical and numerical approaches, in order to obtain the solution with microarcsecond accuracy.
Colloquium on Phobos-Mars Mission, Paris, France, Oct. 23-27, 1989, Proceedings
NASA Astrophysics Data System (ADS)
Blamont, J. E.
A preliminary analysis of results obtained from the Phobos-Mars missions is presented. Topics include solar X-ray observation with the RF-15 instrument, new insights on cosmic gamma-ray bursts from the APEX experiment, EUV observations of solar flares from Mars, short term variability of the power spectrum of 5-min oscillations of the sun, and results of the LET experiment. Plasma waves around Mars, tails of Phobos and Deimos in the solar wind and in the Martian magnetosphere, the HARP plasma experiment onboard the Phobos 2 spacecraft, Martian atmosphere studies from the ISM experiment, low-energy charged particles in near Martian space from SLED and LET experiments aboard the Phobos 2 spacecraft, and submillimeter observations of CO in Mars' atmosphere are also discussed. Results of TV imaging of Phobos, color decorrelation for the Phobos mission camera experiment, slope variations on the surface of Phobos, and an interpretation of the surface brightness of Phobos are given.
Philological Papers: Special Issue Devoted to the Teacher in Nineteenth- and Twentieth-Century Literature and Film. Volume 36. Papers Presented at the West Virginia University's Annual Colloquium (13th, Morgantown, West Virginia, September 29-October 1, 1988).
ERIC Educational Resources Information Center
Singer, Armand E., Ed.
This volume contains papers read at West Virginia University's Colloquium on "The Teacher in Nineteenth- and Twentieth-Century Literature and Film" including the following 12 articles listed with their authors: "A Second Pair of Eyes: The Editor as Teacher" (Hart L. Wegner); "Don Juan Goes to the Movies" (Armand E. Singer); "The Teacher in Jean…
Significant Wilderness Qualities: Can They Be Identified and Monitored? Proceedings of the Annual NOLS [National Outdoor Leadership School] Wilderness Research Colloquium (3rd, Shoshone National Forest, Wyoming, August 10-15, 1987).
ERIC Educational Resources Information Center
Cole, David N., Comp.; Lucas, Robert C., Comp.
This report is a compilation of the papers presented at a colloquium on wilderness management and a synopsis of discussions held during the conference. The conference theme was how to determine and monitor the most significant features and qualities of the wilderness resource. Generally, participants identify solitude; pollution-free air and…
Linguistic Insights in Applied Linguistics. Collection d'"Etudes linguistiques," No. 14. Papers from the Neuchatel Colloquium in Applied Linguistics in collaboration with AIMAV, AILA, CILA, and the University of Neuchatel (2nd, May 25-26, 1973).
ERIC Educational Resources Information Center
Corder, S. P., Ed.; Roulet, E., Ed.
Papers from the 1973 Neuchatel Colloquium in Applied Linguistics are presented. Contents are as follows: "Karttunen's Types of Implication in English and German: A Contrastive Study," W. Abraham; "The Relevance of Generative Semantics for Language Teaching," R. Dirven; "'Be' plus 'ing' Revisited," H. Adamczeski; "The So-Called Deep Structures and…
The 2008 Charles H. Thompson Lecture-Colloquium Presentation: From Du Bois to Obama--The Education of Peoples of African Descent in the United States in the 21st Century
ERIC Educational Resources Information Center
Lee, Carol D.
This article presents the text of a lecture delivered by American Educational Research Association President Carol D. Lee at the 29th Annual Charles H. Thompson Lecture-Colloquium Series which was held on November 5, 2008. In her lecture, Lee discussed several points of similarities between W. E. B. Du Bois and President Barack Obama. These…
Vinculacion Entre La Educacion Y El Mundo Del Trabajo: Informe Final. (Coloquio Regional Caracas, Venezuela, Septiembre 2-6, 1985) = The Linkage Between Education and Employment: Final Report of the Regional Colloquium (Caracas, Venezuela, September 2-6, 1985).
ERIC Educational Resources Information Center
United Nations Educational, Scientific, and Cultural Organization, Santiago (Chile). Regional Office for Education in Latin America and the Caribbean.
At this regional colloquium 13 papers were presented concerning the relationship between education and employment. Themes addressed were: (1) the transformation of the workplace by technology and science; (2) the future of the disadvantaged population as a consequence of the technological revolution; and (3) the resulting changes in the education…
Engineering and Technology Education for the 21st Century. A Report from the Regional Colloquium on Engineering and Technology Education for the 21st Century (Nakhon Ratchasima, Thailand, February 11-14, 1997).
ERIC Educational Resources Information Center
Kettle, Kevin C., Ed.
This colloquium was held with the purposes of promoting cooperation and collaboration among engineering education institutions in the Mekong subregion and establishing the linkage with engineering institutions in France; to promote university-industry collaboration in the field of engineering and technology education; to establish a network of…
Apprendre a vivre ensemble grace a l'enseignement de l'histoire et de la geographie. Rapport final du colloque sur le theme. (Learning To Live Together Thanks to the Teaching of History and Geography. Final Report on a Colloquium on That Theme.) Proceedings of a Colloquium Organized Jointly by the International Bureau of Education (UNESCO) and the University of Geneva (Geneva, Switzerland, June 12, 1998).
ERIC Educational Resources Information Center
Andre, Yves, Ed.; Mouzoune, Abdelkrim, Ed.
These Proceedings contain 14 chapters (or papers) from a colloquium on learning to live together in peaceful co-existence thanks to the teaching of history and geography. All the papers in the Proceedings are in French, but each paper has both an English summary and a Spanish summary. The 14 papers are, as follows: (1) "Introduction" (Yves Andre;…
NASA Technical Reports Server (NTRS)
Pap, Judit M.; Frohlich, Claus; Hudson, Hugh S.
The IAU Colloquium No. 143, 'The Sun as a Variable Star: Solar and Stellar Irradiance Variations', was held June 20-25, 1993, at the Clarion House, Boulder, Colorado. The main objective of this colloquium was to review the most recent results on the observations, theoretical interpretations, empirical and physical models of the variations observed in solar and stellar irradiances. A special emphasis of the colloquium was to discuss the results gained on the climatic impact of solar irradiance variability.
Comets: Gases, ices, grains and plasma
NASA Technical Reports Server (NTRS)
Wilkening, L. L.
The program and abstracts of the 97 papers delivered at the colloquium are presented. Cometary nuclei, comet dust, the coma, ion tails, several comet missions, and cometary origin and evolution were discussed.
Horton, W.; Hu, G.
The origin of plasma turbulence from currents and spatial gradients in plasmas is described and shown to lead to the dominant transport mechanism in many plasma regimes. A wide variety of turbulent transport mechanism exists in plasmas. In this survey the authors summarize some of the universally observed plasma transport rates.
Foster, J.S. Jr.
This patent describes apparatus for producing an electricity neutral ionized gas discharge, termed a plasma, substantially free from contamination with neutral gas particles. The plasma generator of the present invention comprises a plasma chamber wherein gas introduced into the chamber is ionized by a radiofrequency source. A magnetic field is used to focus the plasma in line with an exit. This magnetic field cooperates with a differential pressure created across the exit to draw a uniform and uncontaminated plasma from the plasma chamber.
NASA Astrophysics Data System (ADS)
Laroussi, M.; Kong, M. G.; Morfill, G.; Stolz, W.
Foreword R. Satava and R. J. Barker; Part I. Introduction to Non-equilibrium Plasma, Cell Biology, and Contamination: 1. Introduction M. Laroussi; 2. Fundamentals of non-equilibrium plasmas M. Kushner and M. Kong; 3. Non-equilibrium plasma sources M. Laroussi and M. Kong; 4. Basic cell biology L. Greene and G. Shama; 5. Contamination G. Shama and B. Ahlfeld; Part II. Plasma Biology and Plasma Medicine: 6. Common healthcare challenges G. Isbary and W. Stolz; 7. Plasma decontamination of surfaces M. Kong and M. Laroussi; 8. Plasma decontamination of gases and liquids A. Fridman; 9. Plasma-cell interaction: prokaryotes M. Laroussi and M. Kong; 10. Plasma-cell interaction: eukaryotes G. Isbary, G. Morfill and W. Stolz; 11. Plasma based wound healing G. Isbary, G. Morfill and W. Stolz; 12. Plasma ablation, surgery, and dental applications K. Stalder, J. Woloszko, S. Kalghatgi, G. McCombs, M. Darby and M. Laroussi; Index.
Science and Society Colloquium
Mr. Randi will give an update of his lecture to the American Physical Society on the occasion of his award of the 1989 Forum Prize. The citation said: "for his unique defense of Science and the scientific method in many disciplines, including physics, against pseudoscience, frauds and charlatans. His use of scientific techniques has contributed to refuting suspicious and fraudulent claims of paranormal results. He has contributed significantly to public understanding of important issues where science and society interact". He is a professional magician and author of many books. He worked with John Maddox, the Editor of Nature to investigate the claims of "water with memory".
Seventh NASTRAN User's Colloquium
NASA Technical Reports Server (NTRS)
The general application of finite element methodology and the specific application of NASTRAN to a wide variety of static and dynamic structural problems are described. Topics include: fluids and thermal applications, NASTRAN programming, substructuring methods, unique new applications, general auxiliary programs, specific applications, and new capabilities.
Southeastern Science Policy Colloquium
Humphries, F.
This conference covers four main topics: (1) Southeastern Labor Market and its Impact on Corporate/Industry Development; (2) New Issues for Science and Technology in the Year 2000 and Beyond; (3) The Role of Academia in Developing the Labor Force of the Southeast; and (4) K-12 Education: Challenges for the 21st Century.
Science and Society Colloquium
Mr. Randi will give an update of his lecture to the American Physical Society on the occasion of his award of the 1989 Forum Prize. The citation said: "for his unique defense of Science and the scientific method in many disciplines, including physics, against pseudoscience, frauds and charlatans. His use of scientific techniques has contributed to refuting suspicious and fraudulent claims of paranormal results. He has contributed significantly to public understanding of important issues where science and society interact". He is a professional magician and author of many books. He worked with John Maddox, the Editor of Nature to investigate the claims of "water with memory".
Tenth NASTRAN User's Colloquium
NASA Technical Reports Server (NTRS)
The development of the NASTRAN computer program, a general purpose finite element computer code for structural analysis, was discussed. The application and development of NASTRAN is presented in the following topics: improvements and enhancements; developments of pre and postprocessors; interactive review system; the use of harmonic expansions in magnetic field problems; improving a dynamic model with test data using Linwood; solution of axisymmetric fluid structure interaction problems; large displacements and stability analysis of nonlinear propeller structures; prediction of bead area contact load at the tire wheel interface; elastic plastic analysis of an overloaded breech ring; finite element solution of torsion and other 2-D Poisson equations; new capability for elastic aircraft airloads; usage of substructuring analysis in the get away special program; solving symmetric structures with nonsymmetric loads; evaluation and reduction of errors induced by Guyan transformation.
Colloquium: The neutron lifetime
Greene, Geoffrey L; Wietfeldt, F
The decay of the free neutron into a proton, electron, and antineutrino is the prototype semileptonic weak decay and is the simplest example of nuclear beta decay. It played a key role in the early Universe as it determined the ratio of neutrons to protons during the era of primordial light element nucleosynthesis. Neutron decay is physically related to important processes in solar physics and neutrino detection. The mean neutron lifetime has been the subject of more than 20 major experiments done, using a variety of methods, between 1950 and the present. The most precise recent measurements have stated accuracies approaching 0.1%, but are not in good agreement as they differ by as much as 5 sigma using quoted uncertainties. The history of neutron lifetime measurements is reviewed and the different methods used are described, giving important examples of each. The discrepancies and some systematic issues in the experiments that may be responsible are discussed, and it is shown by means of global averages that the neutron lifetime is likely to lie in the range of 880 884 s. Plans and prospects for future experiments are considered that will address these systematic issues and improve our knowledge of the neutron lifetime.
Jones, M.E.; Winske, D.; Keinigs, R.; Lemons, D.
This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The objective of this project has been to develop a fundamental understanding of dusty plasmas at the Laboratory. While dusty plasmas are found in space in galactic clouds, planetary rings, and cometary tails, and as contaminants in plasma enhanced fabrication of microelectronics, many of their properties are only partially understood. Our work has involved both theoretical analysis and self-consistent plasma simulations to understand basic properties of dusty plasmas related to equilibrium, stability, and transport. Such an understanding can improve the control and elimination of plasma dust in industrial applications and may be important in the study of planetary rings and comet dust tails. We have applied our techniques to the study of charging, dynamics, and coagulation of contaminants in plasma processing reactors for industrial etching and deposition processes and to instabilities in planetary rings and other space plasma environments. The work performed in this project has application to plasma kinetics, transport, and other classical elementary processes in plasmas as well as to plasma waves, oscillations, and instabilities.
Ruth, R.D.; Chen, P.
In this paper we discuss plasma accelerators which might provide high gradient accelerating fields suitable for TeV linear colliders. In particular we discuss two types of plasma accelerators which have been proposed, the Plasma Beat Wave Accelerator and the Plasma Wake Field Accelerator. We show that the electric fields in the plasma for both schemes are very similar, and thus the dynamics of the driven beams are very similar. The differences appear in the parameters associated with the driving beams. In particular to obtain a given accelerating gradient, the Plasma Wake Field Accelerator has a higher efficiency and a lower total energy for the driving beam. Finally, we show for the Plasma Wake Field Accelerator that one can accelerate high quality low emittance beams and, in principle, obtain efficiencies and energy spreads comparable to those obtained with conventional techniques.
PREFACE: 1982 International Conference on Plasma Physics
NASA Astrophysics Data System (ADS)
Wilhelmsson, Hans
second one to (3) Fusion and (4) Laboratory Plasmas. The 1982 International Conference on Plasma Physics was organized by Chalmers University of Technology. It gathered about 500 participants from 40 countries. Large delegations came from the USA, France, West Germany, Japan, the USSR, and India, the number of participants from these countries ranging from 100 to 20. Sweden had about 50 participating scientists. There were a total of about 20 from the other Scandinavian countries. The principal sponsor of the conference was IUPAP, the International Union of Pure and Applied Physics. The conference also had a number of co-sponsors like IAU, the International Astronomical Union, URSI, the International Union of Radio Science, EPS, the European Physical Society, and EURATOM-FUSION. The conference was supported by Swedish Industry and Swedish Research Boards. The previous ICPP, held in Nagoya two years ago, was the first attempt to combine two types of conferences: the Plasma Theory Conference, first held in Kiev in the Soviet Union in 1971, and the Waves and Instabilities Congress, held for the first time in Innsbruck, Austria in 1973. As a consequence of the success of the Nagoya conference it was decided by the International Organizing Committee of the ICPP that the 1982 conference should also be of the combined type. The 1982 ICPP in Göteborg was thus a Joint Conference of the Fifth Kiev International Conference in Plasma Theory and the Fifth International Congress on Waves and Instabilities in Plasmas. During the conference in Göteborg the International Organizing Committee had a meeting and it was decided that also the next International Conference on Plasma Physics will be of the combined type. It will be held in Lausanne, Switzerland in 1984. The International Organizing Committee on the 1982 International Conference on Plasma Physics comprised about 40 plasma physics scientists from all over the world, who represented various sections of plasma physics. I would
A creative approach to the development of an agenda for knowledge utilization: outputs from the 11th international knowledge utilization colloquium (KU 11).
Wilkinson, Joyce E; Rycroft-Malone, Jo; Davies, Huw T O; McCormack, Brendan
A group of researchers and practitioners interested in advancing knowledge utilization met as a colloquium in Belfast (KU 11) and used a "world café" approach to exploit the social capital and shared understanding built up over previous events to consider the research and practice agenda. We considered three key areas of relevance to knowledge use: (1) understanding the nature of research use, influence and impact; (2) blended and collaborative approaches to knowledge production and use; and (3) supporting sustainability and spread of evidence-informed innovations. The approach enabled the development of artifacts that reflected the three areas and these were analyzed using a creative hermeneutic approach. The themes that emerged and which are outlined in this commentary are not mutually exclusive. There was much overlap in the discussions and therefore of the themes, reflecting the complex nature of knowledge translation work. The agenda that has emerged from KU 11 also reflects the participatory and creative approach in which the meeting was structured and focused, and therefore emphasizes the processual, relational and contingent nature of some of the challenges we face. The past 20 years has seen an explosion in activity around understanding KU, and we have learned much about the difficulties. Whilst the agenda for the next decade may be becoming clearer, colloquia such as KU 11, using creative and engaging approaches, have a key role to play in dissecting, articulating and sharing that agenda. In this way, we also build an ever-expanding international community that is dedicated to working towards increasing the chances of success for better patient care. PMID:22849391
Bilinguisme et biculturalisme: Theories et pratiques professionnelles. Actes du 2eme colloque d'orthophomie/logopedie (Neuchatel, 17-18 septembre, 1992). (Bilingualism and Biculturalism: Theories and Professional Practices. Colloquium on Orthophony/Logopedy (2nd, Neuchatel, Switzerland, September 17-18, 1992)).
ERIC Educational Resources Information Center
Py, Bernard, Ed.
The conference papers from a colloquium on issues in bilingualism and biculturalism include: "Le bilinguisme et biculturalisme: essai de definition" ("Bilingualism and Biculturalism: Attempt at Definition") (Francois Grosjean); "La variation individuelle dans l'acquisition d'une langue seconde" ("Individual Variation in Second Language…
Wang, Zhehui; Barnes, Cris W.
There has been invented an apparatus for acceleration of a plasma having coaxially positioned, constant diameter, cylindrical electrodes which are modified to converge (for a positive polarity inner electrode and a negatively charged outer electrode) at the plasma output end of the annulus between the electrodes to achieve improved particle flux per unit of power.
Furth, H.P.; Chambers, E.S.
BS>A method is given for ion cyclotron resonance heatthg of a magnetically confined plasma by an applied radio-frequency field. In accordance with the invention, the radiofrequency energy is transferred to the plasma without the usual attendent self-shielding effect of plasma polarlzatlon, whereby the energy transfer is accomplished with superior efficiency. More explicitly, the invention includes means for applying a radio-frequency electric field radially to an end of a plasma column confined in a magnetic mirror field configuration. The radio-frequency field propagates hydromagnetic waves axially through the column with the waves diminishing in an intermediate region of the column at ion cyclotron resonance with the fleld frequency. In such region the wave energy is converted by viscous damping to rotational energy of the plasma ions. (AEC)
Baker, W.R.
A device is described for establishing and maintaining a high-energy, rotational plasma for use as a fast discharge capacitor. A disc-shaped, current- conducting plasma is formed in an axinl magnetic field and a crossed electric field, thereby creating rotational kinetic enengy in the plasma. Such energy stored in the rotation of the plasma disc is substantial and is convertible tc electrical energy by generator action in an output line electrically coupled to the plasma volume. Means are then provided for discharging the electrical energy into an external circuit coupled to the output line to produce a very large pulse having an extremely rapid rise time in the waveform thereof. (AE C)
NASA Astrophysics Data System (ADS)
Smarandache, Florentin
``Unmatter Plasma'' is a novel form of plasma, exclusively made of matter and its antimatter counterpart. An experiment (2015) on matter-antimatter plasma [or unmatter plasma] was recently successful at the Astra Gemini laser facility at the Rutherford Appleton Laboratory, Oxford, United Kingdom. The experiment that was made has produced electron-positron plasma. The positron is the antimatter of the electron, having an opposite charge of the electron, but the other properties are the same. Unmatter is considered as a combination of matter and antimatter. For example electron-positron is a type of unmatter. We coined the word ``unmatter'' (2004) that means neither matter nor antimatter, but something in between. Besides matter and antimatter there may exist unmatter (as a new form of matter) in accordance with the neutrosophy theory that between an entity and its opposite there exist intermediate entities.
NASA Technical Reports Server (NTRS)
Alfven, H.
Traditionally the views on the cosmic environent have been based on observations in the visual octave of the electromagnetic spectrum, during the last half-century supplemented by infrared and radio observations. Space research has opened the full spectrum. Of special importance are the X-ray-gamma-ray regions, in which a number of unexpected phenomena have been discovered. Radiations in these regions are likely to originate mainly from magnetised cosmic plasmas. Such a medium may also emit synchrotron radiation which is observable in the radio region. If a model of the universe is based on the plasma phenomena mentioned it is found that the plasma universe is drastically different from the traditional visual universe. Information about the plasma universe can also be obtained by extrapolation of laboratory experiments and magnetospheric in situ measurements of plasmas. This approach is possible because it is likely that the basic properties of plasmas are the same everywhere. In order to test the usefulness of the plasma universe model it is applied to cosmogony. Such an approach seems to be rather successful. For example, the complicated structure of the Saturnian C ring can be accounted for. It is possible to reconstruct certain phenomena 4 to 5 billions of years ago with an accuracy of better than 1%.
Cosmic Magnetic Fields (IAU S259)
NASA Astrophysics Data System (ADS)
Strassmeier, Klaus G.; Kosovichev, Alexander G.; Beckman, John E.
Preface K. G. Strassmeier, A. G. Kosovichev and J. E. Beckman; Organising committee; Conference photograph; Conference participants; Session 1. Interstellar magnetic fields, star-forming regions and the Death Valley Takahiro Kudoh and Elisabeta de Gouveia Dal Pino; Session 2. Multi-scale magnetic fields of the Sun; their generation in the interior, and magnetic energy release Nigel O. Weiss; Session 3. Planetary magnetic fields and the formation and evolution of planetary systems and planets; exoplanets Karl-Heinz Glassmeier; Session 4. Stellar magnetic fields: cool and hot stars Swetlana Hubrig; Session 5. From stars to galaxies and the intergalactic space Dimitry Sokoloff and Bryan Gaensler; Session 6. Advances in methods and instrumentation for measuring magnetic fields across all wavelengths and targets Tom Landecker and Klaus G. Strassmeier; Author index; Object index; Subject index.
ESO at the IAU General Assembly
NASA Astrophysics Data System (ADS)
The 25th General Assembly of the International Astronomical Union was held in Sydney,Australia, from 13-24 July 2003. For two weeks the world of professional astronomy descended on Darling Harbour. In the early days it was used for receiving fresh produce and timber from Parramatta and the north coast, but with time had become a somewhat derelict dock area. Following massive redevelopment of the old wharves in the course of the 1980s, it now constitutes a spectacular example of contemporary urban renovation, with shopping malls, hotels, restaurants, museums and other leisure facilities, as well as the magnificent Sydney Convention and Exhibition Centre (SCEC).
Organic Matter in Space (IAU S251)
NASA Astrophysics Data System (ADS)
Kwok, Sun; Sanford, Scott
Preface; From the local organising committee; Organising committee; Conference participants; Opening address of Symposium 251 C. Cesarsky; Session I. Observations of organic compounds beyond the Solar System William Irvine, Ewine van Dishoeck, Yvonne Pendleton and Hans Olofsson; Session II. Organic compounds within the Solar System Scott Sandford, Ernst Zinner and Dale Cruikshank; Session III. Laboratory analogues of organic compounds in space Max Bernstein and Thomas Henning; Banquet speech; Author index; Object index.
Organic Matter in Space (IAU S251)
NASA Astrophysics Data System (ADS)
Kwok, Sun; Sanford, Scott
Preface; From the local organising committee; Organising committee; Conference participants; Opening address of Symposium 251 C. Cesarsky; Session I. Observations of organic compounds beyond the Solar System William Irvine, Ewine van Dishoeck, Yvonne Pendleton and Hans Olofsson; Session II. Organic compounds within the Solar System Scott Sandford, Ernst Zinner and Dale Cruikshank; Session III. Laboratory analogues of organic compounds in space Max Bernstein and Thomas Henning; Banquet speech; Author index; Object index.
NASA Astrophysics Data System (ADS)
Mamajek, Eric E.; Soderblom, David R.; Wyse, Rosemary F. G.
Preface; Part I. The Milky Way and Nearby Galaxies Guido De Marchi; Part II. Ages of Young Stars Michal Simon; Part III. Models of Stars and Tests of Models Sylvie Vauclair; Part IV. Globular Clusters and Old Open Clusters Rosemary Wyse; Part V. White Dwarfs Robert Rood; Part VI. Brown Dwarfs Michael Liu; Part VII. Age-related Properties of Solar-type Stars Fred Walter; Part VIII. Asteroseismology and the Sun Jeff Valenti; Part IX. Nucleochronology John Stauffer; Author index; Object index; Subject index.
On April 19, 2010 AIA observed one of the largest prominence eruptions in years. The huge structure erupts, but a great deal of the plasma (hundreds of millions of tons) is unable to escape the gra...
NASA Technical Reports Server (NTRS)
Hintze, Paul E.
NASA's Kennedy Space Center has developed two solvent-free precision cleaning techniques: plasma cleaning and supercritical carbon dioxide (SCCO2), that has equal performance, cost parity, and no environmental liability, as compared to existing solvent cleaning methods.
X-ray, EUV, UV and Optical Emissivities of Asrophysical Plasmas
NASA Astrophysics Data System (ADS)
Raymond, John C.
In this reporting period we have concentrated on evaluating the available collision strength and dielectronic recombination data and on incorporating the iron L-shell collision strengths of Duane Liedahl (computed with HULLAC) in the code. We have published the first major results, an evaluation of the M-shell collisional data for iron based on SERTS and EUVE data. We have critically compared the existing X-ray emission codes as a follow-on to the Napa HEAD meeting in 1994. We are using ASCA spectra and EUVE spectra to further test the reliability of the codes by testing whether a single set of model parameters can account for the entire observed spectrum. We have written a review of the emission spectra of hot astrophysical plasmas emphasizing some lesser-known processes. We have also considered the effects of non-Maxwellian electron velocity distributions on emission line spectra. N. Brickhouse presented a colloquium on the use of spectral models for EUV Astrophysics at Auburn U in February 1995. All three of us participated actively in the Rates, Codes, & Astrophysics Workshop in July 1995, sponsored by the AXAF Science Center, serving on the organizing committee, chairing a session on atomic rate uncertainties, and presenting papers on photoionized plasmas and spectral fitting approaches.
Baker, W.R.; Brathenahl, A.; Furth, H.P.
A device for producing a confined high temperature plasma is described. In the device the concave inner surface of an outer annular electrode is disposed concentrically about and facing the convex outer face of an inner annular electrode across which electrodes a high potential is applied to produce an electric field there between. Means is provided to create a magnetic field perpendicular to the electric field and a gas is supplied at reduced pressure in the area therebetween. Upon application of the high potential, the gas between the electrodes is ionized, heated, and under the influence of the electric and magnetic fields there is produced a rotating annular plasma disk. The ionized plasma has high dielectric constant properties. The device is useful as a fast discharge rate capacitor, in controlled thermonuclear research, and other high temperature gas applications. (AEC)
Gow, J.D.; Wilcox, J.M.
A device is designed for producing and confining highenergy plasma from which neutrons are generated in copious quantities. A rotating sheath of electrons is established in a radial electric field and axial magnetic field produced within the device. The electron sheath serves as a strong ionizing medium to gas introdueed thereto and also functions as an extremely effective heating mechanism to the resulting plasma. In addition, improved confinement of the plasma is obtained by ring magnetic mirror fields produced at the ends of the device. Such ring mirror fields are defined by the magnetic field lines at the ends of the device diverging radially outward from the axis of the device and thereafter converging at spatial annular surfaces disposed concentrically thereabout. (AFC)
NASA Technical Reports Server (NTRS)
Armstrong, J. W.
Radio communication with space probes requires sending signals through the Earth's ionosphere and usually the solar wind. During planetary flybys, the signal may also pass through the ionosphere of another planet. These ionized media can perturb the radio signal in a variety of ways. Examples of these perturbations are variations in the electrical length between the spacecraft and the ground station, Faraday rotation of linearly polarized signals, amplitude and phase scintillations, and spectral and angular broadening. These plasma effects can have undesirable influences on telemetry performance and thus need to be understood from a communications engineering viewpoint. The plasma effects are, however, useful from a scientific viewpoint, since the effects on the communications link can often be inverted to estimate the physical conditions in the plasma.
BOOK REVIEW : Future Professional Communication in Astronomy. Proceedings of the Colloquium held at the Palace of the Academies, Brussels, 10-13 June 2007
NASA Astrophysics Data System (ADS)
Duerbeck, H. W.; Heck, A.; Houziaux, L.
These are the timely and well-edited proceedings of a colloquium dealing with the present state and the future of "communication'' in astronomy. While communication in the past was mainly restricted to printed journals, conferences and colloquia, things have changed dramatically in the last decades. Journals have gone online, and runs of paper copies are slowly declining. 25 astronomers and representatives of various publishing institutions met in Brussels in June 2007 to discuss the future and the different options of information communication and -exchange. 16 contributions are supplemented by summaries of discussions held at the meeting. After a general overview of one of the organizers, who has played a key role in various aspects of information exchange, several representatives discuss future plans of their publications: K.B. Marvel presents the AAS journals (ApJ parts I and II, ApJS, AJ, which are just being transferred from the University of Chicago Press to Institute of Physics Publishing). P. Murdin represents the RAS and its main journal, the MNRAS. "Open Access'' is of course one of the key words of this conference. Producing a journal (either on paper or electronically) is expensive. For the AAS journals, these costs are shared between authors andsubscribers. Future plans are to abandon "paper copies'' at all, although "printable pages'' will continue to be provided. For MNRAS, it is the subscribers who pay. And if it would have "open access'', authors would have to be charged for publication.Some research funding agencies demand that scientific results that they have sponsored should appear online, and freely available (at least after a certaintime). Various approaches were outlined by representatives of publishers (Wiley-Blackwell, Springer, Elsevier, EDP Sciences). S. Plaszczynski introduced a project for "open access'' in the field of high energy physics. To replace "repositories'' and collections of "preprints'' that may have never made it to the
Wilcox, J.M.; Baker, W.R.
This invention is a magnetohydrodynamic device for generating a highly ionized ion-electron plasma at a region remote from electrodes and structural members, thus avoiding contamination of the plasma. The apparatus utilizes a closed, gas-filled, cylindrical housing in which an axially directed magnetic field is provided. At one end of the housing, a short cylindrical electrode is disposed coaxially around a short axial inner electrode. A radial electrical discharge is caused to occur between the inner and outer electrodes, creating a rotating hydromagnetic ionization wave that propagates aiong the magnetic field lines toward the opposite end of the housing. A shorting switch connected between the electrodes prevents the wave from striking the opposite end of the housing. (AEC)
Ninth NASTRAN (R) Users' Colloquium
NASA Technical Reports Server (NTRS)
The general application of finite element methodology and the specific application of NASTRAN to a wide variety of static and dynamic structural problems is addressed. Comparison with other approaches and new methods of analysis with nastran are included.
Thirteenth NASTRAN (R) Users' Colloquium
NASA Technical Reports Server (NTRS)
The application of finite element methods in engineering is discussed and the use of NASTRAN is compared with other approaches. Specific applications, pre- and post-processing or auxiliary programs, and additional methods of analysis with NASTRAN are covered.
Sixth NASTRAN (R) Users' Colloquium
NASA Technical Reports Server (NTRS)
Papers are presented on NASTRAN programming, and substructuring methods, as well as on fluids and thermal applications. Specific applications and capabilities of NASTRAN were also delineated along with general auxiliary programs.
Third International Colloquium on Mars
NASA Technical Reports Server (NTRS)
Abstracts of papers concerning the geology and geophysics of Mars, volcanism on Mars, the Mars atmosphere, and the long term history of the atmosphere-cap-regolith volatile regime are presented. Formation of the Mars surface, climatology, gravity and magnetism, atmospheric boundary layers, and interpretation of Viking imagery and Earth-based observations are considered.
Fifteenth NASTRAN (R) Users' Colloquium
NASA Technical Reports Server (NTRS)
Numerous applications of the NASA Structural Analysis (NASTRAN) computer program, a general purpose finite element code, are discussed. Additional features that can be added to NASTRAN, interactive plotting of NASTRAN data on microcomputers, mass modeling for bars, the design of wind tunnel models, the analysis of ship structures subjected to underwater explosions, and buckling analysis of radio antennas are among the topics discussed.
Twelfth NASTRAN (R) Users' Colloquium
NASA Technical Reports Server (NTRS)
NASTRAN is a large, comprehensive, nonproprietary, general purpose finite element computer code for structural analysis. The Twelfth Users' Colloquim provides some comprehensive papers on the application of finite element methods in engineering, comparisons with other approaches, unique applications, pre and post processing or auxiliary programs, and new methods of analysis with NASTRAN.
First colloquium in biological sciences
Scott, W.N.; Strand, F.L.
This book contains over 150 papers. Some of the topics include: biochemistry, biological sciences, biomedical sciences, biophysics, and microbiology. There are also plenary lectures on such areas as genetic dissection of viral virulence, and gonadal hormones and brain development.
Twentieth NASTRAN (R) Users' Colloquium
NASA Technical Reports Server (NTRS)
The proceedings of the conference are presented. Some comprehensive general papers are presented on applications of finite elements in engineering, comparisons with other approaches, unique applications, pre and post processing with other auxiliary programs, and new methods of analysis with NASTRAN.
Colloquium: Water's controversial glass transitions
NASA Astrophysics Data System (ADS)
Amann-Winkel, Katrin; Böhmer, Roland; Fujara, Franz; Gainaru, Catalin; Geil, Burkhard; Loerting, Thomas
Water is the most common and, judged from its numerous anomalous properties, the weirdest of all known liquids and the complexity of its pressure-temperature map is unsurpassed. A major obstacle on the way to a full understanding of water's structure and dynamics is the hard-to-explore territory within this map, colloquially named the no man's land. Many experiments suggest that just before stepping across its low-temperature border, amorphous ices undergo glass-to-liquid transitions while other interpretations emphasize the importance of underlying disordered (nano)crystalline states. Prospects for reconciling the conflicting views regarding the nature of water's glass transitions are discussed.
"Colloquium": A Conversation about Excellence.
ERIC Educational Resources Information Center
Nist, Elizabeth A.
Small community or vocational colleges often face the problem of trying to run quality academic programs with adjunct or part-time faculty who have little contact with the regular faculty and little say in policy-making. The Utah Valley Community College writing program, which successfully combined regular and adjunct faculty in planning and…
IRIS Mission Operations Director's Colloquium
NASA Technical Reports Server (NTRS)
Carvalho, Robert; Mazmanian, Edward A.
Pursuing the Mysteries of the Sun: The Interface Region Imaging Spectrograph (IRIS) Mission. Flight controllers from the IRIS mission will present their individual experiences on IRIS from development through the first year of flight. This will begin with a discussion of the unique nature of IRISs mission and science, and how it fits into NASA's fleet of solar observatories. Next will be a discussion of the critical roles Ames contributed in the mission including spacecraft and flight software development, ground system development, and training for launch. This will be followed by experiences from launch, early operations, ongoing operations, and unusual operations experiences. The presentation will close with IRIS science imagery and questions.
Division E Commission 49: Interplanetary Plasma and Heliosphere
NASA Astrophysics Data System (ADS)
Mann, Ingrid; Manoharan, P. K.; Gopalswamy, Natchimuthuk; Briand, Carine; Chashei, Igor V.; Gibson, Sarah E.; Lario, David; Hanaoka, Yoichiro; Malandraki, Olga; Kontar, Eduard; Richardson, John D.
After a little more than forty years of work related to the interplanetary plasma and the heliosphere the IAU's Commission 49 was formally discontinued in 2015. The commission started its work when the first spacecraft were launched to measure the solar wind in-situ away from Earth orbit, both inward and outward from 1 AU. It now hands over its activities to a new commission during an era of space research when Voyager 1 measures in-situ the parameters of the local interstellar medium at the edge of the heliosphere. The commission will be succeeded by C.E3 with a similar area of responsibility but with more focused specific tasks that the community intends to address during the coming several years. This report includes a short description of the motivation for this commission and of the historical context. It then describes work from 2012 to 2015 during the present solar cycle 24 that has been the weakest in the space era so far. It gave rise to a large number of studies on solar energetic particles and cosmic rays. Other studies addressed e.g. the variation of the solar wind structure and energetic particle fluxes on long time scales, the detection of dust in the solar wind and the Voyager measurements at the edge of the heliosphere. The research is based on measurements from spacecraft that are at present operational and motivated by the upcoming Solar Probe + and Solar Orbiter missions to explore the vicinity of the Sun. We also report here the progress on new and planned radio instruments and their importance for heliospheric studies. Contributors to this report are Carine Briand, Yoichiro Hanaoka, Eduard Kontar, David Lario, Ingrid Mann, John D. Richardson.
The unexpected confluence of plasma physics and climate science: On the lives and legacies of Norman Rostoker and Sherry Rowland
NASA Astrophysics Data System (ADS)
Mackey, Katherine R. M.
The Norman Rostoker Memorial Symposium brought together approximately 150 attendees to share their recent work and to reflect on the contributions of Norman Rostoker to the field of plasma physics and the advancement of fusion as a source of renewable clean energy. The field has changed considerably in a few short decades, with theoretical advances and technological innovations evolving in lock step. Over those same decades, our understanding of human induced climate change has also evolved; measurable changes in Earth's physical, chemical, and biological processes have already been observed, and these will likely intensify in the coming decades. Never before has the need for clean energy been more pronounced, or the need for transformative solutions more pressing. As scientists work with legislators, journalists, and the public to take actions to address the threat of climate change, there is much to be learned from the legacies of innovators like Norman Rostoker, who have tackled complex problems with scientific insight and determination even when the odds were stacked against them. I write this from the perspective on an Earth system scientist who studies photosynthesis and the biogeochemistry of the oceans, and my statements about plasma physics and Norman Rostoker are based on information I gathered from the colloquium and from many enjoyable conversations with his friends and colleagues.
NASA Technical Reports Server (NTRS)
Cheng, D. Y.
Converging, coaxial accelerator electrode configuration operates in vacuum as plasma gun. Plasma forms by periodic injections of high pressure gas that is ionized by electrical discharges. Deflagration mode of discharge provides acceleration, and converging contours of plasma gun provide focusing.
... limited. Home Visit Global Sites Search Help? Plasma Free Metanephrines Share this page: Was this page helpful? ... known as: Plasma Metanephrines Formal name: Fractionated Plasma Free Metanephrines (Metanephrine and Normetanephrine) Related tests: Catecholamines ; Urine ...
NASA Astrophysics Data System (ADS)
Correll, Don; Heeter, Robert; Alvarez, Mitch
In response to many inquiries for a list of plasma terms, a database driven Plasma Dictionary website (plasmadictionary.llnl.gov) was created that allows users to submit new terms, search for specific terms or browse alphabetic listings. The Plasma Dictionary website contents began with the Fusion & Plasma Glossary terms available at the Fusion Energy Educational website (fusedweb.llnl.gov). Plasma researchers are encouraged to add terms and definitions. By clarifying the meanings of specific plasma terms, it is envisioned that the primary use of the Plasma Dictionary website will be by students, teachers, researchers, and writers for (1) Enhancing literacy in plasma science, (2) Serving as an educational aid, (3) Providing practical information, and (4) Helping clarify plasma writings. The Plasma Dictionary website has already proved useful in responding to a request from the CRC Press (www.crcpress.com) to add plasma terms to its CRC physics dictionary project (members.aol.com/physdict/).
Progress on plasma accelerators
Chen, P.
Several plasma accelerator concepts are reviewed, with emphasis on the Plasma Beat Wave Accelerator (PBWA) and the Plasma Wake Field Accelerator (PWFA). Various accelerator physics issues regarding these schemes are discussed, and numerical examples on laboratory scale experiments are given. The efficiency of plasma accelerators is then revealed with suggestions on improvements. Sources that cause emittance growth are discussed briefly.
Communication through plasma sheaths
Korotkevich, A. O.; Newell, A. C.; Zakharov, V. E.
We wish to transmit messages to and from a hypersonic vehicle around which a plasma sheath has formed. For long distance transmission, the signal carrying these messages must be necessarily low frequency, typically 2 GHz, to which the plasma sheath is opaque. The idea is to use the plasma properties to make the plasma sheath appear transparent.
Motley, R.W.; Glanz, J.
A device is described for coupling RF power (a plasma sweeper) from RF power introducing means to a plasma having a magnetic field associated therewith comprises at least one electrode positioned near the plasma and near the RF power introducing means. Means are described for generating a static electric field at the electrode directed into the plasma and having a component substantially perpendicular to the plasma magnetic field such that a non-zero vector cross-product of the electric and magnetic fields exerts a force on the plasma causing the plasma to drift.
NASA Astrophysics Data System (ADS)
Galeev, A. A.; Sudan, R. N.
The basic physics of classical ideal plasmas is presented in reviews of recent theoretical and experimental investigations, with an emphasis on nonlinear interactions violating the assumptions of weak turbulence. Topics examined include Kolmogorov spectra, parametric instabilities in magnetoactive plasmas, collapse and self-focusing of Langmuir waves, collective dissipation and transport, spontaneous reconnection of magnetic-field lines in a collisionless plasma, collective-beam/plasma interaction, numerical particle simulations, diagnostic techniques based on the interaction of electromagnetic radiation with a plasma, diagnostics for magnetically confined high-temperature plasmas, and relativistic electron-beam/plasma interaction with self-fields. Diagrams, graphs, spectra, and drawings of experimental apparatus are provided.
NASA Astrophysics Data System (ADS)
Ahedo, Eduardo
Plasma thrusters are challenging the monopoly of chemical thrusters in space propulsion. The specific energy that can be deposited into a plasma beam is orders of magnitude larger than the specific chemical energy of known fuels. Plasma thrusters constitute a vast family of devices ranging from already commercial thrusters to incipient laboratory prototypes. Figures of merit in plasma propulsion are discussed. Plasma processes and conditions differ widely from one thruster to another, with the pre-eminence of magnetized, weakly collisional plasmas. Energy is imparted to the plasma via either energetic electron injection, biased electrodes or electromagnetic irradiation. Plasma acceleration can be electrothermal, electrostatic or electromagnetic. Plasma-wall interaction affects energy deposition and erosion of thruster elements, and thus is central for thruster efficiency and lifetime. Magnetic confinement and magnetic nozzles are present in several devices. Oscillations and turbulent transport are intrinsic to the performances of some thrusters. Several thrusters are selected in order to discuss these relevant plasma phenomena.
Industrial plasmas in academia
NASA Astrophysics Data System (ADS)
Hollenstein, Ch; Howling, AA; Guittienne, Ph; Furno, I.
The present review, written at the occasion of the 2014 EPS Innovation award, will give a short overview of the research and development of industrial plasmas within the last 30 years and will also provide a first glimpse into future developments of this important topic of plasma physics and plasma chemistry. In the present contribution, some of the industrial plasmas studied at the CRPP/EPFL at Lausanne are highlighted and their influence on modern plasma physics and also discharge physics is discussed. One of the most important problems is the treatment of large surfaces, such as that used in solar cells, but also in more daily applications, such as the packaging industry. In this contribution, the advantages and disadvantages of some of the most prominent plasmas such as capacitively- and inductively-coupled plasmas are discussed. Electromagnetic problems due to the related radio frequency and its consequences on the plasma reactor performance, and also dust formation due to chemical reactions in plasma, are highlighted. Arcing and parasitic discharges occurring in plasma reactors can lead to plasma reactor damages. Some specific problems, such as the gas supply of a large area reactor, are discussed in more detail. Other topics of interest have been dc discharges such as those used in plasma spraying where thermal plasmas are applied for advanced material processing. Modern plasma diagnostics make it possible to investigate sparks in electrical discharge machining, which surprisingly show properties of weakly-coupled plasmas. Nanosecond dielectric barrier discharge plasmas have been applied to more speculative topics such as applications in aerodynamics and will surely be important in the future for ignition and combustion. Most of the commonly-used plasma sources have been shown to be limited in their performance. Therefore new, more effective plasma sources are urgently required. With the recent development of novel resonant network antennas for new
5th International conference on Physics and Astrophysics of Quark Gluon Plasma
NASA Astrophysics Data System (ADS)
Sinha, Bikash; Alam, Jan-E.; Nayak, Tapan K.
The 5th International Conference on Physics and Astrophysics of Quark Gluon Plasma (ICPAQGP 2005) was held on 8 - 12 February 2005 at the Variable Energy Cyclotron Centre and Saha Institute of Nuclear Physics campus, Kolkata, India. The conference was enriched by the august presence of about 300 participants representing 18 countries across the globe. It had plenary talks and oral presentations, which form a part of these proceedings. Besides invited and contributed talks there were also a large number of poster presentations. The conference was energized by discussions of fresh experimental data from RHIC on strong elliptic flow, jet quenching, single photon spectra etc. Moreover, new theoretical results were brought to the discussion forum during this conference. Colour glass condensates, hydrodynamical flow, jet quenching and sQGP were intensely debated by the participants. The highlight of ICPAQGP 2005 was the presentation of fresh experimental results from the RHIC-IV run. The ICPAQGP series, since its inception in 1988, has placed emphasis on the role of quark matter in the fields of astrophysics and cosmology. The subsequent conferences held in 1993, 1997, 2001 and 2005 had also retained this focus. The conference was preceded by a Fest Colloquium in honour of Professor Bikash Sinha. Professor Sinha, regarded as the pioneer in establishing quark gluon plasma research in India, has successfully encouraged a group of young Indian researchers to devote themselves wholeheartedly to QGP research - both theoretical and experimental. Members of the International Advisory Committee played a pivotal role mainly in the selection of speakers. The contributions of the Organizing Committee in all aspects, from selecting the contributory talks posters down to arranging local hospitality, were much appreciated. We thank the members of both committees for making ICPAQGP 2005 an interesting platform for scientific deliberation. The ICPAQGP 2005 was supported financially by
Fundamentals of Plasma Physics
NASA Astrophysics Data System (ADS)
Bellan, Paul M.
Preface; 1. Basic concepts; 2. The Vlasov, two-fluid, and MHD models of plasma dynamics; 3. Motion of a single plasma particle; 4. Elementary plasma waves; 5. Streaming instabilities and the Landau problem; 6. Cold plasma waves in a magnetized plasma; 7. Waves in inhomogeneous plasmas and wave energy relations; 8. Vlasov theory of warm electrostatic waves in a magnetized plasma; 9. MHD equilibria; 10. Stability of static MHD equilibria; 11. Magnetic helicity interpreted and Woltjer-Taylor relaxation; 12. Magnetic reconnection; 13. Fokker-Planck theory of collisions; 14. Wave-particle nonlinearities; 15. Wave-wave nonlinearities; 16. Non-neutral plasmas; 17. Dusty plasmas; Appendix A. Intuitive method for vector calculus identities; Appendix B. Vector calculus in orthogonal curvilinear coordinates; Appendix C. Frequently used physical constants and formulae; Bibliography; References; Index.
Experiments with nonneutral plasmas
NASA Astrophysics Data System (ADS)
O'Neil, T. M.
Selected experiments with nonneutral plasmas are discussed. These include the laser cooling of a pure ion plasma to a crystalline state, a measurement of the Salpeter enhancement factor for fusion in a strongly correlated plasma and the measurement of thermally excited plasma waves. Also, discussed are experiments that demonstrate Landau damping, trapping and plasma wave echoes in the 2D ExB drift flow of a pure electron plasma, which is isomorphic to the 2D ideal flow (incompressible and inviscid flow) of a neutral fluid.
International movement of plasma and plasma contracting.
Farrugia, A
Plasma fractionation is a global business characterised by technological stability, increasing consolidation and a high level of regulatory oversight. All these factors affect the ease with which plasma derivatives can be accessed in the world market. As domestic regulatory measures in the first world blood economies become increasingly resonant to the precautionary approach, the availability of plasma as a raw material, as well as its cost, become an increasingly significant component in the cost of the final product. This decreases the amount of plasma which fractionators are able to allocate for export activities. Also, regulatory standards in the country of manufacture will reflect priorities in that country which may not be similar to those in export markets, but which will affect entry to those markets. While many countries possess a fractionation capacity, the limiting factor in supply worldwide is the amount of plasma available, and nationalistic drivers for each country to have its own plant are inimical to product safety and supply. Rather, the provision of sufficient supplies of domestic plasma should be the focus of resource allocation, with a choice of an appropriate contract fractionator. However, contract fractionation too may be affected by domestic considerations unrelated to the needs of the country of plasma origin. This chapter will review the global plasma market and the influences on plasma and plasma product movement across national borders. Problems in ensuring adequate safety and supply will be identified, and some tentative approaches to the amelioration of current barriers to the provision of plasma derivatives will be outlined. PMID:16050160
Moss, S.J.; Jolly, A.M.; Tighe, B.J.
The rates of plasma oxidation have been measured for homopolymers of several monomers and for copolymers of methyl methacrylate with styrene and vinyl naphthalene. Their results show that relatively small amounts of the aromatic component in the copolymer convey substantially increased resistance to plasma oxidation. Current knowledge of the mechanisms of plasma oxidation is reviewed and new mechanistic explanations are suggested. The implications for improved design of plasma-developable resists systems are considered.
NASA Astrophysics Data System (ADS)
Suplee, Curt
Preface; 1. The fourth state of matter; 2. The music and dance of plasmas; 3. The Sun-Earth connection; 4. Bringing the Sun to Earth: the story of controlled thermonuclear fusion; 5. The cosmic plasma theater: galaxies, stars, and accretion disks; 6. Putting plasmas to work; Index.
A reconfigurable plasma antenna
Kumar, Rajneesh; Bora, Dhiraj
An experiment aimed at investigating the antenna properties of different plasma structures of a plasma column as a reconfigurable plasma antenna, is reported. A 30 cm long plasma column is excited by surface wave, which acts as a plasma antenna. By changing the operating parameters, e.g., working pressure, drive frequency, input power, radius of glass tube, length of plasma column, and argon gas, single plasma antenna (plasma column) can be transformed to multiple small antenna elements (plasma blobs). It is also reported that number, length, and separation between two antenna elements can be controlled by operating parameters. Moreover, experiments are also carried out to study current profile, potential profile, conductivity profile, phase relations, radiation power patterns, etc. of the antenna elements. The effect on directivity with the number of antenna elements is also studied. Findings of the study indicate that entire structure of antenna elements can be treated as a phased array broadside vertical plasma antenna, which produces more directive radiation pattern than the single plasma antenna as well as physical properties and directivity of such antenna can be controlled by operating parameters. The study reveals the advantages of a plasma antenna over the conventional antenna in the sense that different antennas can be formed by tuning the operating parameters.
NASA Astrophysics Data System (ADS)
Brownell, J. H.; Freeman, B. L.
Plasma focus driven target implosions are simulated using hydrodynamic-burn codes. Support is given to the idea that the use of a target in a plasma focus should allow 'impedance matching' between the fuel and gun, permitting larger fusion yields from a focus-target geometry than the scaling laws for a conventional plasma focus would predict.
... microorganisms to which the body is exposed. In plasma cell disorders, one clone of plasma cells multiplies uncontrollably. As a result, this clone ... a light chain and heavy chain). These abnormal plasma cells and the ... produce are limited to one type, and levels of other types of antibodies ...
Plasma and magnetospheric research
NASA Technical Reports Server (NTRS)
Comfort, R. H.; Horwitz, J. L.
Research activities on the following topics were summarized: (1) software for the Space Plasma computer Analysis Network (SPAN), (2) plasmaspheric field-aligned temperature gradients, (3) the shift in spacecraft potential as a function of plasma density, (4) plasma flow, (5) the Fabry-Perot interferometer, and (6) the Differential Ion Flux Probe (DIFP).
Aerospatiale industrial thermal plasma activities
NASA Astrophysics Data System (ADS)
Labrot, Maxime
Details of nontransferred arc torches, plasma systems in industrial use and operational plasma applications are listed. A plasma application on a foundry cupola is detailed. The setting up of a plasma system is described. Research and development activities are summarized.
Physics of Partially Ionized Plasmas
NASA Astrophysics Data System (ADS)
Krishan, Vinod
Figures; Preface; 1. Partially ionized plasmas here and everywhere; 2. Multifluid description of partially ionized plasmas; 3. Equilibrium of partially ionized plasmas; 4. Waves in partially ionized plasmas; 5. Advanced topics in partially ionized plasmas; 6. Research problems in partially ionized plasmas; Supplementary matter; Index.
Samarian, A. A.; Boufendi, L.; Mikikian, M.
The review of the first detailed experimental and theoretical studies of complex plasma in RF discharge afterglow is presented. The studies have been done in a frame of FAST collaborative research project between Complex Plasma Laboratory of the University of Sydney and the GREMI laboratory of Universite d'Orleans. We examined the existing models of plasma decay, presents experimental observations of dust dynamics under different afterglow complex plasma conditions, presents the experimental data obtained (in particular the presence of positively charged particles in discharge afterglow), discusses the use of dust particles as a probe to study the diffusion losses in afterglow plasmas.
Moir, Ralph W.
A mirror plasma apparatus which utilizes shielding by arc discharge to form a blanket plasma and lithium walls to reduce neutron damage to the wall of the apparatus. An embodiment involves a rotating liquid lithium blanket for a tandem mirror plasma apparatus wherein the first wall of the central mirror cell is made of liquid lithium which is spun with angular velocity great enough to keep the liquid lithium against the first material wall, a blanket plasma preventing the lithium vapor from contaminating the plasma.
Fisch, N.J.
A plasma in contact with an external source of power, especially a source that interacts specifically with high-velocity electrons, exhibits transport properties, such as conductivity, different from those of an isolated plasma near thermal equilibrium. This is true even when the bulk of the particles in the driven plasma are near thermal equilibrium. To describe the driven plasma we derive an adjoint equation to the inhomogeneous, linearized, dynamic Boltzmann equation. The Green's functions for a variety of plasma responses can then be generated. It is possible to modify the Chapman-Enskog expansion in order to incorporate the response functions derived here.
NASA Astrophysics Data System (ADS)
Alexeff, Igor
This presentation summarizes an extensive program on plasma antennas. Plasma antennas are just as effective as metal antennas. In addition, they can transmit, receive and reflect lower frequency signals while being transparent to higher frequency signals. When de-energized, they electrically disappear. Plasma noise does not appear to be a problem. New technology that has been developed include a method of operating at high plasma density at minimal power consumption, a novel technique of noise reduction, and a method of opening a plasma window in a plasma microwave barrier on a time scale of microseconds rather than the usual time scale of milliseconds due to plasma decay. We are at present testing an intelligent plasma antenna in which a plasma ``window'' in a circular plasma barrier surrounding an antenna rotates azimuthally, seeking a radio transmitter. When located, a computer locks onto the transmitter. When the transmitter is de-energized, the plasma window recommences scanning. Commercial interest is strong, with invited papers being presented for 4 years in succession at the SMi Stealth Conference in London, UK, an operating model on permanent exhibition at the Booze-Allen headquarters in Alexandria, VA, and strong interest from Lockheed-Martin. In collaboration with Ted Anderson, Haleakala R&D Corp.; Esmaeil Farshi, Fred Dyer, Jeffrey Peck, Eric Pradeep, Nanditha Pulasani, and Naresh Karnam, University of Tennessee.
NASA Astrophysics Data System (ADS)
von Woedtke, Th.; Reuter, S.; Masur, K.; Weltmann, K.-D.
Plasma medicine is an innovative and emerging field combining plasma physics, life science and clinical medicine. In a more general perspective, medical application of physical plasma can be subdivided into two principal approaches. (i) "Indirect" use of plasma-based or plasma-supplemented techniques to treat surfaces, materials or devices to realize specific qualities for subsequent special medical applications, and (ii) application of physical plasma on or in the human (or animal) body to realize therapeutic effects based on direct interaction of plasma with living tissue. The field of plasma applications for the treatment of medical materials or devices is intensively researched and partially well established for several years. However, plasma medicine in the sense of its actual definition as a new field of research focuses on the use of plasma technology in the treatment of living cells, tissues, and organs. Therefore, the aim of the new research field of plasma medicine is the exploitation of a much more differentiated interaction of specific plasma components with specific structural as well as functional elements or functionalities of living cells. This interaction can possibly lead either to stimulation or inhibition of cellular function and be finally used for therapeutic purposes. During recent years a broad spectrum of different plasma sources with various names dedicated for biomedical applications has been reported. So far, research activities were mainly focused on barrier discharges and plasma jets working at atmospheric pressure. Most efforts to realize plasma application directly on or in the human (or animal) body for medical purposes is concentrated on the broad field of dermatology including wound healing, but also includes cancer treatment, endoscopy, or dentistry. Despite the fact that the field of plasma medicine is very young and until now mostly in an empirical stage of development yet, there are first indicators of its enormous
Electronegative Plasma Instabilities in Pulsed Plasmas
NASA Astrophysics Data System (ADS)
Pribyl, Patrick; Gekelman, Walter
Modern inductively coupled plasma reactors can all be operated in unstable configurations, although in many cases normal precautions result in quiescent stable operation. However, electronegative gases that are important for etch processes have a series of instabilities that occur at process relevant conditions. These have been studied since the 1990s, but are becoming a much more important today as plasma reactors are being pushed to produce ever finer features, and tight control of the etch process is becoming crucial. A device at UCLA was designed to simulate industrial reactors used in semiconductor processing. Various gas mixtures are programmable (Ar, SF6, O2). ICP coils in different configurations are driven by pulsed RF generators operating separately from 400 kHz to 40 MHz. A stainless steel ``chuck'' assembly can be positioned at a variable height, either with a wafer and RF bias, or with direct DC bias to directly program sheath voltage. A computer controlled automated probe drive can access the entire volume above the substrate. The probe can be a Langmuir probe, a ``Bdot'' probe, or an emissive probe the latter used for more accurate determination of plasma potential. A microwave interferometer is available to measure line-averaged electron density. Optical emission can be diagnosed using a half or 1 meter spectrometer. We describe work with electronegative gases to characterize and potentially stabilize the plasma against ionization instabilities using pulsed plasmas. Work supported by NSF and done at the Basic Plasma Science Facility.
Plasma Biomedicine in Orthopedics
NASA Astrophysics Data System (ADS)
Hamaguchi, Satsohi
Various effects of plasmas irradiation on cells, tissues, and biomaterials relevant for orthopedic applications have been examined. For direct application of plasmas to living cells or tissues, dielectric barrier discharges (DBDs) with helium flows into ambient air were used. For biomaterial processing, on the other hand, either helium DBDs mentioned above or low-pressure discharges generated in a chamber were used. In this presentation, plasma effects on cell proliferation and plasma treatment for artificial bones will be discussed. First, the conditions for enhanced cell proliferation in vitro by plasma applications have been examined. The discharge conditions for cell proliferation depend sensitively on cell types. Since cell proliferation can be enhanced even when the cells are cultured in a plasma pre-treated medium, long-life reactive species generated in the medium by plasma application or large molecules (such as proteins) in the medium modified by the plasma are likely to be the cause of cell proliferation. It has been found that there is strong correlation between (organic) hydroperoxide generation and cell proliferation. Second, effects of plasma-treated artificial bones made of porous hydroxyapatite (HA) have been examined in vitro and vivo. It has been found that plasma treatment increases hydrophilicity of the surfaces of microscopic inner pores, which directly or indirectly promotes differentiation of mesenchymal stem cells introduced into the pores and therefore causes faster bone growth. The work has been performed in collaboration with Prof. H. Yoshikawa and his group members at the School of Medicine, Osaka University.
Plasma Physics: An Introductory Course
NASA Astrophysics Data System (ADS)
Dendy, R. O.
Preface; Introduction R. O. Dendy; 1. Plasma particle dynamics R. J. Hastie; 2. Plasma kinetic theory J. A. Elliott; 3. Waves in plasmas J. P. Doughtery; 4. Magnetohydrodynamics K. I. Hopcraft; 5. Turbulence in fluids and fusion plasmas F. A. Haas; 6. Finite-dimensional dynamics and chaos T. J. Mullin; 7. Computational plasma physics J. W. Eastwood; 8. Tokomak experiments D. C. Robinson and M. R. O'Brien; 9. Magnetospheric plasmas: Part I Basic processes in the solar system D. A. Bryant; Part II Microprocesses R. L. Bingham; 10. Solar plasmas R. A. Hood; 11. Gravitational plasmas J. J. Binney; 12. Laser plasmas A. R. Bell; 13. Industrial plasmas P. C. Johnson; 14. Transport in magnetically confined plasmas T. E. Stringer; 15. Radio-frequency plasma heating R. A. Cairns; 16. Boundary plasmas G. McCracken; 17. How to build a tokomak T. N. Todd; 18. Survey of fusion plasma physics R. S. Pease; Index.
Advanced plasma diagnostics for plasma processing
NASA Astrophysics Data System (ADS)
Malyshev, Mikhail Victorovich
A new, non-intrusive, non-perturbing diagnostic method was developed that can be broadly applied to low pressure, weakly ionized plasmas and glow discharges-trace rare gases optical emission spectroscopy (TRG-OES). The method is based on a comparison of intensities of atomic emission from trace amounts of inert gases (He, Ne, Ar, Kr, and Xe) that are added to the discharge to intensities calculated from the theoretical model. The model assumes a Maxwellian electron energy distribution function (EEDF), computes the population of emitting levels both from the ground state and the metastable states of rare gases, and from the best fit between theory and experiment determines electron temperature (Te). Subject to conditions, TRG-OES can also yield electron density or its upper or lower limit. From the comparison of the emission from levels excited predominantly by high energy electrons to that excited by low energy electrons, information about the EEDF can be obtained. The use of TRG-OES also allows a traditionally qualitative actinometry technique (determination of concentration of radical species in plasma through optical emission) to become a precise quantitative method by including Te and rare gases metastables effects. A combination of TRG-OES, advanced actinometry, and Langmuir probe measurements was applied to several different plasma reactors and regimes of operation. Te measurements and experiments to correct excitation cross section were conducted in a laboratory helical resonator. Two chamber configuration of a commercial (Lam Research) metal etcher were studied to determine the effects of plasma parameters on plasma-induced damage. Two different methods (RF inductive coupling and ultra-high frequency coupling) for generating a plasma in a prototype reactor were also studied. Pulsed plasmas, a potential candidate to eliminate the plasma-induced damage to microelectronics devices that occurs in manufacturing due to differential charging of the wafer, have
Intrator, Thomas P.
This introduction will define the plasma fourth state of matter, where we find plasmas on earth and beyond, and why they are useful. There are applications to many consumer items, fusion energy, scientific devices, satellite communications, semiconductor processing, spacecraft propulsion, and more. Since 99% of our observable universe is ionized gas, plasma physics determines many important features of astrophysics, space physics, and magnetosphere physics in our solar system. We describe some plasma characteristics, examples in nature, some useful applications, how to create plasmas. A brief introduction to the theoretical framework includes the connection between kinetic and fluid descriptions, quasi neutrality, Debye shielding, ambipolar electric fields, some plasma waves. Hands-on demonstrations follow. More complete explanations will follow next week.
NASA Astrophysics Data System (ADS)
Krasheninnikov, S. I.; Kukushkin, A. S.; Pshenov, A. A.
Regime with the plasma detached from the divertor targets (detached divertor regime) is a natural continuation of the high recycling conditions to higher density and stronger impurity radiation loss. Both the theoretical considerations and experimental data show clearly that the increase of the impurity radiation loss and volumetric plasma recombination causes the rollover of the plasma flux to the target when the density increases, which is the manifestation of detachment. Plasma-neutral friction (neutral viscosity effects), although important for the sustainment of high density/pressure plasma upstream and providing the conditions for efficient recombination and power loss, is not directly involved in the reduction of the plasma flux to the targets. The stability of detachment is also discussed.
Cha, Seunghee; Park, Young-Seok
This review describes the contemporary aspects of plasma application in dentistry. Previous studies on plasma applications were classified into two categories, surface treatment and direct applications, and were reviewed, respectively according to the approach. The current review discussed modification of dental implant surface, enhancing of adhesive qualities, enhancing of polymerization, surface coating and plasma cleaning under the topics of surface treatment. Microbicidal activities, decontamination, root canal disinfection and tooth bleaching were reviewed as direct applications with other miscellaneous ones. Non-thermal atmospheric pressure plasma was of particular focus since it is gaining considerable attention due to the possibility for its use in living tissues. Future perspectives have also been discussed briefly. Although it is still not popular among dentists, plasma has shown promises in several areas of dentistry and is now opening a new era of plasma dentistry. PMID:27030818
Voltage Amplification using Plasma
Farias, E. E.; Cavalcanti, G. H.; Santiago, M. A. M.
The purpose of this work is to present experimental results about voltage amplification using plasma produced by a simple neon lamp, series connected with a signal generator and discrete circuit elements. The main advantage of employing plasma as an amplifier is due to its ability to drive larger power and potentially to operate in a larger frequency range compared with traditional amplifiers. Our results show that both, the voltage gain and the frequency range where the gain is bigger than one, are related to the plasma density which may be adjusted by a proper control of electrical discharge conditions. The plasma produced into the neon lamp exhibits a diode characteristic that is the principal responsible by the nonlinear plasma response. The amplification occurs when the plasma shows a negative conductance. In this regime the lamp works as an active amplifier and voltage gain higher than 18 was obtained.
PES fabric plasma modification
NASA Astrophysics Data System (ADS)
Vatuňa, T.; Špatenka, P.; Píchal, J.; Koller, J.; Aubrecht, L.; Wiener, J.
Polyester ranks the upper position in the world fiber production — nearly 54% of the total production of synthetic fibers. Troubles connected with minimizing of the textile hydrophobicity are usually being solved by the textile fibers' surface chemical modification, but from ecological point of view modification of fabric with low temperature plasma is superior to classical chemical wet processes. Application of various plasmas for PES treatment has been already described. To compare the effectiveness of different plasma sources we performed a series of experiment both in RF and MW plasmas. For working gas nitrogen, oxygen and their mixtures were employed. Internal plasma control was provided by measurement of optical emission spectra. The hydrophilicity degree was determined by the drop test. Paper discusses optimal conditions of the PES fabric plasma treatment.
NASA Technical Reports Server (NTRS)
Comfort, Richard H.; Horwitz, James L.
During the course of this grant, work was performed on a variety of topics and there were a number of significant accomplishments. A summary of these accomplishments is included. The topics studied include empirical model data base, data reduction for archiving, semikinetic modeling of low energy plasma in the inner terrestrial magnetosphere and ionosphere, O(+) outflows, equatorial plasma trough, and plasma wave ray-tracing studies. A list of publications and presentations which have resulted from this research is also included.
NASA Astrophysics Data System (ADS)
Meyer, T. N.
Thermal plasma systems are providing a major new technology for basic ironmaking with the added benefits of process reductant flexibility and potential for reduced capital cost. Industrial scale plasma systems (1,000 to 8,000 kW) have been installed and operated in both pilot and production facilities. Present operational data have confirmed the viability of plasma systems as industrially acceptable methods for high temperature processing at both new and existing ironmaking facilities.
Akamatsu, Yukinao; Yamamoto, Naoki
We study the collective modes in relativistic electromagnetic or quark-gluon plasmas with an asymmetry between left- and right-handed chiral fermions, based on the recently formulated kinetic theory with Berry curvature corrections. We find that there exists an unstable mode, signaling the presence of a plasma instability. We argue the fate of this "chiral plasma instability" including the effect of collisions, and briefly discuss its relevance in heavy ion collisions and compact stars. PMID:23952387
NASA Astrophysics Data System (ADS)
Cretenot, Didier; Vanrenterghem, Jacques; Labrot, Maxime; Pineau, Didier
The use of arc plasma for waste destruction is addressed. Types of treatable waste, processes for liquid and solid or pasty wastes, and the present state of these techniques in France are described. The efficiency of arc plasma technology in the destruction of liquid organochlorinated waste compounds in commercial size units, particularly mobile units, is demonstrated. Many trials with solid waste demonstrate that plasmas are a highly efficient solution.
Titan's Variable Plasma Interaction
NASA Astrophysics Data System (ADS)
Ledvina, S. A.; Brecht, S. H.
Cassini observations have found that the plasma and magnetic field conditions upstream of Titan are far more complex than they were thought to be after the Voyager encounter. Rymer et al., (2009) used the Cassini Plasma Spectrometer (CAPS) electron observations to classify the plasma conditions along Titan's orbit into 5 types (Plasma Sheet, Lobe, Mixed, Magnetosheath and Misc.). Nemeth et al., (2011) found that the CAPS ion observations could also be separated into the same plasma regions as defined by Rymer et al. Additionally the T-96 encounter found Titan in the solar wind adding a sixth classification. Understanding the effects of the variable upstream plasma conditions on Titan's plasma interaction and the evolution of Titan's ionosphere/atmosphere is one of the main objectives of the Cassini mission. To compliment the mission we perform hybrid simulations of Titan's plasma interaction to examine the effects of the incident plasma distribution function and the flow velocity. We closely examine the results on Titan's induced magnetosphere and the resulting pickup ion properties.
Solid expellant plasma generator
NASA Technical Reports Server (NTRS)
Stone, Nobie H. (Inventor); Poe, Garrett D. (Inventor); Rood, Robert (Inventor)
An improved solid expellant plasma generator has been developed. The plasma generator includes a support housing, an electrode rod located in the central portion of the housing, and a mass of solid expellant material that surrounds the electrode rod within the support housing. The electrode rod and the solid expellant material are made of separate materials that are selected so that the electrode and the solid expellant material decompose at the same rate when the plasma generator is ignited. This maintains a point of discharge of the plasma at the interface between the electrode and the solid expellant material.
Plasma Processing Of Hydrocarbon
Grandy, Jon D; Peter C. Kong; Brent A. Detering; Larry D. Zuck
The Idaho National Laboratory (INL) developed several patented plasma technologies for hydrocarbon processing. The INL patents include nonthermal and thermal plasma technologies for direct natural gas to liquid conversion, upgrading low value heavy oil to synthetic light crude, and to convert refinery bottom heavy streams directly to transportation fuel products. Proof of concepts has been demonstrated with bench scale plasma processes and systems to convert heavy and light hydrocarbons to higher market value products. This paper provides an overview of three selected INL patented plasma technologies for hydrocarbon conversion or upgrade.
NASA Technical Reports Server (NTRS)
Ferguson, Dale C.
Photovoltaic arrays interact with the low earth orbit (LEO) space plasma in two fundamentally different ways. One way is the steady collection of current from the plasma onto exposed conductors and semiconductors. The relative currents collected by different parts of the array will then determine the floating potential of the spacecraft. In addition, these steady state collected currents may lead to sputtering or heating of the array by the ions or electrons collected, respectively. The second kind of interaction is the short time scale arc into the space plasma, which may deplete the array and/or spacecraft of stored charge, damage solar cells, and produce EMI. Such arcs only occur at high negative potentials relative to the space plasma potential, and depend on the steady state ion currents being collected. New high voltage solar arrays being incorporated into advanced spacecraft and space platforms may be endangered by these plasma interactions. Recent advances in laboratory testing and current collection modeling promise the capability of controlling, and perhaps even using, these space plasma interactions to enable design of reliable high voltage space power systems. Some of the new results may have an impact on solar cell spacing and/or coverslide design. Planned space flight experiments are necessary to confirm the models of high voltage solar array plasma interactions. Finally, computerized, integrated plasma interactions design tools are being constructed to place plasma interactions models into the hands of the spacecraft designer.
Princeton Plasma Physics Laboratory
Not Available
This report discusses the following topics: principal parameters achieved in experimental devices fiscal year 1990; tokamak fusion test reactor; compact ignition tokamak; Princeton beta experiment- modification; current drive experiment-upgrade; international collaboration; x-ray laser studies; spacecraft glow experiment; plasma processing: deposition and etching of thin films; theoretical studies; tokamak modeling; international thermonuclear experimental reactor; engineering department; project planning and safety office; quality assurance and reliability; technology transfer; administrative operations; PPPL patent invention disclosures for fiscal year 1990; graduate education; plasma physics; graduate education: plasma science and technology; science education program; and Princeton Plasma Physics Laboratory reports fiscal year 1990.
EDITORIAL: Plasma jets and plasma bullets Plasma jets and plasma bullets
NASA Astrophysics Data System (ADS)
Kong, M. G.; Ganguly, B. N.; Hicks, R. F.
Plasma plumes, or plasma jets, belong to a large family of gas discharges whereby the discharge plasma is extended beyond the plasma generation region into the surrounding ambience, either by a field (e.g. electromagnetic, convective gas flow, or shock wave) or a gradient of a directionless physical quantity (e.g. particle density, pressure, or temperature). This physical extension of a plasma plume gives rise to a strong interaction with its surrounding environment, and the interaction alters the properties of both the plasma and the environment, often in a nonlinear and dynamic fashion. The plasma is therefore not confined by defined physical walls, thus extending opportunities for material treatment applications as well as bringing in new challenges in science and technology associated with complex open-boundary problems. Some of the most common examples may be found in dense plasmas with very high dissipation of externally supplied energy (e.g. in electrical, optical or thermal forms) and often in or close to thermal equilibrium. For these dense plasmas, their characteristics are determined predominantly by strong physical forces of different fields, such as electrical, magnetic, thermal, shock wave, and their nonlinear interactions [1]. Common to these dense plasma plumes are significant macroscopic plasma movement and considerable decomposition of solid materials (e.g. vaporization). Their applications are numerous and include detection of elemental traces, synthesis of high-temperature materials and welding, laser--plasma interactions, and relativistic jets in particle accelerators and in space [2]-[4]. Scientific challenges in the understanding of plasma jets are exciting and multidisciplinary, involving interweaving transitions of all four states of matter, and their technological applications are wide-ranging and growing rapidly. Using the Web of Science database, a search for journal papers on non-fusion plasma jets reveals that a long initial phase up
Self-energized plasma compressor. [for compressing plasma discharged from coaxial plasma generator
NASA Technical Reports Server (NTRS)
Shriver, E. L.; Igenbergs, E. B. (Inventor)
The self-energized plasma compressor is described which compresses plasma discharged from a coaxial plasma generator. The device includes a helically shaped coil which is coaxially aligned with the center axis of the coaxial plasma generator. The plasma generator creates a current through the helical coil which, in turn, generates a time varying magnetic field that creates a force which acts radially upon the plasma. The coaxial plasma generator and helical coil move the plasma under high pressure and temperature to the narrow end of the coil. Positioned adjacent to the narrow end of the coil are beads which are engaged by the plasma to be accelerated to hypervelocities for simulating meteoroids.
EDITORIAL: Plasma jets and plasma bullets Plasma jets and plasma bullets
NASA Astrophysics Data System (ADS)
Kong, M. G.; Ganguly, B. N.; Hicks, R. F.
Plasma plumes, or plasma jets, belong to a large family of gas discharges whereby the discharge plasma is extended beyond the plasma generation region into the surrounding ambience, either by a field (e.g. electromagnetic, convective gas flow, or shock wave) or a gradient of a directionless physical quantity (e.g. particle density, pressure, or temperature). This physical extension of a plasma plume gives rise to a strong interaction with its surrounding environment, and the interaction alters the properties of both the plasma and the environment, often in a nonlinear and dynamic fashion. The plasma is therefore not confined by defined physical walls, thus extending opportunities for material treatment applications as well as bringing in new challenges in science and technology associated with complex open-boundary problems. Some of the most common examples may be found in dense plasmas with very high dissipation of externally supplied energy (e.g. in electrical, optical or thermal forms) and often in or close to thermal equilibrium. For these dense plasmas, their characteristics are determined predominantly by strong physical forces of different fields, such as electrical, magnetic, thermal, shock wave, and their nonlinear interactions [1]. Common to these dense plasma plumes are significant macroscopic plasma movement and considerable decomposition of solid materials (e.g. vaporization). Their applications are numerous and include detection of elemental traces, synthesis of high-temperature materials and welding, laser--plasma interactions, and relativistic jets in particle accelerators and in space [2]-[4]. Scientific challenges in the understanding of plasma jets are exciting and multidisciplinary, involving interweaving transitions of all four states of matter, and their technological applications are wide-ranging and growing rapidly. Using the Web of Science database, a search for journal papers on non-fusion plasma jets reveals that a long initial phase up
NASA Astrophysics Data System (ADS)
Volokitin, G. G.; Skripnikova, N. K.; Sinitsyn, V. A.; Volokitin, O. G.; Shekhovtsov, V. V.; Vaschenko, S. P.; Kuz'min, V. I.
Plasma technology was developed to create protective-decorative coatings on the wood surfaces. Experimental investigation on applying the protective coating using the low-temperature plasma energy as well as studies of the distribution of temperature fields over the section of the treated workpiece have been carried out, and the calculated results have been compared with the experimental data.
NASA Astrophysics Data System (ADS)
Heijmans, Lucas; Nijdam, Sander
In plasma particle lofting, macroscopic particles are picked up from a surface by an electric force. This force originates from a plasma that charges both the surface and any particle on it, leading to an electric force that pushes particles off the surface. This process has been suggested as a novel cleaning technique in modern high-tech applications, because it has intrinsic advantages over more traditional methods. Its development is, however, limited by a lack of knowledge of the underlying physics. Although the lofting has been demonstrated before, there are neither numerical nor experimental quantitative measures of it. Especially determining the charge deposited by a plasma on a particle on a surface proves difficult. We have developed a novel experimental method using a ``probe force.'' This allows us to, for the first time, quantitatively measure the plasma lofting force. By applying this method to different plasma conditions we can identify the important plasma parameters, allowing us to tailor a plasma for specific cleaning applications. Additionally, the quantitative result can help in the development of new models for the electron and ion currents through a plasma sheath.
Carlson, G.A.; Baldwin, D.E.; Barr, W.L.
The two-year Mirror Advanced Reactor Study (MARS) has resulted in the conceptual design of a commercial, electricity-producing fusion reactor based on tandem mirror confinement. The physics basis for the MARS reactor was developed through work in two highly coupled areas of plasma engineering: magnetics and plasma performance.
More, R.M.
Recent experiments with high-power pulsed lasers have strongly encouraged the development of improved theoretical understanding of highly charged ions in a dense plasma environment. This work examines the theory of dense plasmas with emphasis on general rules which govern matter at extreme high temperature and density. 106 refs., 23 figs.
NASA Technical Reports Server (NTRS)
Dr. Tom Markusic, a propulsion research engineer at the Marshall Space Flight Center (MSFC), adjusts a diagnostic laser while a pulsed plasma thruster (PPT) fires in a vacuum chamber in the background. NASA/MSFC's Propulsion Research Center (PRC) is presently investigating plasma propulsion for potential use on future nuclear-powered spacecraft missions, such as human exploration of Mars.
"Angular" plasma cell cheilitis.
da Cunha Filho, Roberto Rheingantz; Tochetto, Lucas Baldissera; Tochetto, Bruno Baldissera; de Almeida, Hiram Larangeira; Lorencette, Nádia Aparecida; Netto, José Fillus
Plasma cell cheilitis is an extremely rare disease, characterized by erythematous-violaceous, ulcerated and asymptomatic plaques, which evolve slowly. The histological characteristics include dermal infiltrate composed of mature plasmocytes. We report a case of Plasma cell angular cheilitis in a 58-year-old male, localized in the lateral oral commissure. PMID:24656273
Lerner, E.J.
A report on the Russian stationary plasma thrusters having plasma accelerated to high velocities by electrical and magnetic forces is described. For specific impulses of 15-20 km/sec, optimal for such applications as satellite station keeping and orbital transfer, a unit supplying 0.05 N from a 2-kW input has a 30-cm-diameter nozzle.
NASA Astrophysics Data System (ADS)
Braithwaite, Nicholas
I agree with Raoul Franklin (November p22) that although the quest for controlled thermonuclear fusion opened up a new branch of plasma physics, the field itself is considerably older, dating back at least as far as 1928 when Irving Langmuir coined the term "plasma" to describe a neutral, ionized gas.
Ward, P.P.; Dybwad, G.L.
The Plasma Technology Directory has two main goals: (1) promote, coordinate, and share plasma technology experience and equipment within the Department of Energy; and (2) facilitate technology transfer to the commercial sector where appropriate. Personnel are averaged first by Laboratory and next by technology area. The technology areas are accelerators, cleaning and etching deposition, diagnostics, and modeling.
Triggered plasma opening switch
Mendel, C W
A triggerable opening switch for a very high voltage and current pulse includes a transmission line extending from a source to a load and having an intermediate switch section including a plasma for conducting electrons between transmission line conductors and a magnetic field for breaking the plasma conduction path and magnetically insulating the electrons when it is desired to open the switch.
Triggered plasma opening switch
Mendel, Clifford W.
A triggerable opening switch for a very high voltage and current pulse includes a transmission line extending from a source to a load and having an intermediate switch section including a plasma for conducting electrons between transmission line conductors and a magnetic field for breaking the plasma conduction path and magnetically insulating the electrons when it is desired to open the switch.
Partially ionized plasmas, including the Third Symposium on Uranium Plasmas
NASA Technical Reports Server (NTRS)
Krishnan, M.
Fundamentals of both electrically and fission generated plasmas are discussed. Research in gaseous fuel reactors using uranium hexafluoride is described and other partially ionized plasma applications are discussed.
NASA Astrophysics Data System (ADS)
Beklemishev, A. D.
A new scheme of plasma thruster is proposed. It is based on axial acceleration of rotating magnetized plasmas in magnetic field with helical corrugation. The idea is that the propellant ionization zone can be placed into the local magnetic well, so that initially the ions are trapped. The E × B rotation is provided by an applied radial electric field that makes the setup similar to a magnetron discharge. Then, from the rotating plasma viewpoint, the magnetic wells of the helically corrugated field look like axially moving mirror traps. Specific shaping of the corrugation can allow continuous acceleration of trapped plasma ions along the magnetic field by diamagnetic forces. The accelerated propellant is expelled through the expanding field of magnetic nozzle. By features of the acceleration principle, the helical plasma thruster may operate at high energy densities but requires a rather high axial magnetic field, which places it in the same class as the VASIMR® rocket engine.
Beklemishev, A. D.
A new scheme of plasma thruster is proposed. It is based on axial acceleration of rotating magnetized plasmas in magnetic field with helical corrugation. The idea is that the propellant ionization zone can be placed into the local magnetic well, so that initially the ions are trapped. The E × B rotation is provided by an applied radial electric field that makes the setup similar to a magnetron discharge. Then, from the rotating plasma viewpoint, the magnetic wells of the helically corrugated field look like axially moving mirror traps. Specific shaping of the corrugation can allow continuous acceleration of trapped plasma ions along the magnetic field by diamagnetic forces. The accelerated propellant is expelled through the expanding field of magnetic nozzle. By features of the acceleration principle, the helical plasma thruster may operate at high energy densities but requires a rather high axial magnetic field, which places it in the same class as the VASIMR{sup ®} rocket engine.
Savage, Mark E.; Mendel, Jr., Clifford W.
A command triggered plasma opening switch assembly using an amplification stage. The assembly surrounds a coaxial transmission line and has a main plasma opening switch (POS) close to the load and a trigger POS upstream from the main POS. The trigger POS establishes two different current pathways through the assembly depended on whether it has received a trigger current pulse. The initial pathway has both POS's with plasma between their anodes and cathodes to form a short across the transmission line and isolating the load. The final current pathway is formed when the trigger POS receives a trigger current pulse which energizes its fast coil to push the conductive plasma out from between its anode and cathode, allowing the main transmission line current to pass to the fast coil of the main POS, thus pushing its plasma out the way so as to establish a direct current pathway to the load.
Chang, C.C.
A method is given for the superfast thermalization of plasma by shock conversion of the kinetic energy stored in rotating plasma rings or plasmoids colliding at near supersonic speeds in a containment field to heat energy in the resultant confined plasma mass. The method includes means for generating rotating plasmoids at the opposite ends of a Pyrotron or Astron containment field. The plasmoids are magnetically accelerated towards each other into the opposite ends of time containment field. During acceleration of the plasmoids toward the center of the containment field, the intensity of the field is sequentially increased to adiabatically compress the plasmoids and increase the plasma energy. The plasmoids hence collide with a violent shock at the eenter of the containment field, causing the substantial kinetic energy stored in the plasmoids to be converted to heat in the resultant plasma mass. (AEC)
Henderson, O.A.
An ion-electron plasma heating apparatus of the pinch tube class was developed wherein a plasma is formed by an intense arc discharge through a gas and is radially constricted by the magnetic field of the discharge. To avoid kink and interchange instabilities which can disrupt a conventional arc shortiy after it is formed, the apparatus is a pinch tube with a flat configuration for forming a sheet of plasma between two conductive plates disposed parallel and adjacent to the plasma sheet. Kink instabilities are suppressed by image currents induced in the conductive plates while the interchange instabilities are neutrally stable because of the flat plasma configuration wherein such instabilities may occur but do not dynamically increase in amplitude. (AEC)
NASA Technical Reports Server (NTRS)
Gurnett, Donald A.
An overview is given of spacecraft observations of plasma waves in the solar system. In situ measurements of plasma phenomena have now been obtained at all of the planets except Mercury and Pluto, and in the interplanetary medium at heliocentric radial distances ranging from 0.29 to 58 AU. To illustrate the range of phenomena involved, we discuss plasma waves in three regions of physical interest: (1) planetary radiation belts, (2) planetary auroral acceleration regions and (3) the solar wind. In each region we describe examples of plasma waves that are of some importance, either due to the role they play in determining the physical properties of the plasma, or to the unique mechanism involved in their generation.
NASA Astrophysics Data System (ADS)
Zurbuchen, Thomas H.; Gershman, Daniel J.
During the history of space exploration, ever improving instruments have continued to enable new measurements and discoveries. Focusing on plasma sensors, we examine the processes by which such new instrument innovations have occurred over the past decades. Due to risk intolerance prevalent in many NASA space missions, innovations in plasma instrumentation occur primarily when heritage systems fail to meet science requirements, functional requirements as part of its space platform, or design constraints. We will review such innovation triggers in the context of the design literature and with the help of two case studies, the Fast Imaging Plasma Spectrometer on MErcury Surface, Space ENvironment, GEochemistry, and Ranging and the Fast Plasma Investigation on Magnetosphere Multiscale. We will then discuss the anticipated needs for new plasma instrument innovations to enable the science program of the next decade.
Weakly relativistic plasma expansion
Fermous, Rachid Djebli, Mourad
Plasma expansion is an important physical process that takes place in laser interactions with solid targets. Within a self-similar model for the hydrodynamical multi-fluid equations, we investigated the expansion of both dense and under-dense plasmas. The weakly relativistic electrons are produced by ultra-intense laser pulses, while ions are supposed to be in a non-relativistic regime. Numerical investigations have shown that relativistic effects are important for under-dense plasma and are characterized by a finite ion front velocity. Dense plasma expansion is found to be governed mainly by quantum contributions in the fluid equations that originate from the degenerate pressure in addition to the nonlinear contributions from exchange and correlation potentials. The quantum degeneracy parameter profile provides clues to set the limit between under-dense and dense relativistic plasma expansions at a given density and temperature.
Dense Hypervelocity Plasma Jets
NASA Astrophysics Data System (ADS)
Witherspoon, F. Douglas; Case, Andrew; Phillips, Michael W.
High velocity dense plasma jets are under continued experimental development for a variety of fusion applications including refueling, disruption mitigation, rotation drive, and magnetized target fusion. The technical goal is to accelerate plasma slugs of density >10^17 cm-3 and total mass >100 micrograms to velocities >200 km/s. The approach utilizes symmetrical injection of very high density plasma into a coaxial EM accelerator having a tailored cross-section geometry to prevent formation of the blow-by instability. Injected plasma is generated by electrothermal capillary discharges using either cylindrical capillaries or a newer toroidal spark gap arrangement that has worked at pressures as low as 3.5 x10-6 Torr in bench tests. Experimental plasma data will be presented for a complete 32 injector accelerator system recently built for driving rotation in the Maryland MCX experiment which utilizes the cylindrical capillaries, and also for a 50 spark gap test unit currently under construction.
Burnouf, Thierry
Protein products fractionated from human plasma are an essential class of therapeutics used, often as the only available option, in the prevention, management, and treatment of life-threatening conditions resulting from trauma, congenital deficiencies, immunologic disorders, or infections. Modern plasma product production technology remains largely based on the ethanol fractionation process, but much has evolved in the last few years to improve product purity, to enhance the recovery of immunoglobulin G, and to isolate new plasma proteins, such as alpha1-protease inhibitor, von Willebrand factor, and protein C. Because of the human origin of the starting material and the pooling of 10,000 to 50,000 donations required for industrial processing, the major risk associated to plasma products is the transmission of blood-borne infectious agents. A complete set of measures--and, most particularly, the use of dedicated viral inactivation and removal treatments--has been implemented throughout the production chain of fractionated plasma products over the last 20 years to ensure optimal safety, in particular, and not exclusively, against HIV, hepatitis B virus, and hepatitis C virus. In this review, we summarize the practices of the modern plasma fractionation industry from the collection of the raw plasma material to the industrial manufacture of fractionated products. We describe the quality requirements of plasma for fractionation and the various treatments applied for the inactivation and removal of blood-borne infectious agents and provide examples of methods used for the purification of the various classes of plasma protein therapies. We also highlight aspects of the good manufacturing practices and the regulatory environment that govern the whole chain of production. In a regulated and professional environment, fractionated plasma products manufactured by modern processes are certainly among the lowest-risk therapeutic biological products in use today. PMID:17397761
Camelopardalids (IAU#451) from comet 209P/LINEAR
NASA Astrophysics Data System (ADS)
Jenniskens, Peter
Since shortly after the comet's discovery in 2004, the close encounter of comet 209P/LINEAR with Earth on 2014 May 29 was highly anticipated as an opportunity to measure past activity of the comet. Only five days earlier, Earth would encounter ejecta from the 18th, 19th and 20th centuries. The outburst was observed from 7-8 km altitude during a SETI Institute sponsored airborne observing campaign. 21 Camelopardalids were detected, for an equivalent peak ZHR˜ 13±4 /h. The meteors were faint, with high magnitude distribution index χ = 3.7±0.5 in the -1 to +5 magnitude range, which translates to a differential mass distribution index of s = 2.42±0.15 (0.003-4 g) and a differential size distribution index of α = 5.3±0.4 (0.2-2 cm). The meteors fragmented excessively towards the end of their trajectory. Twenty trajectories were triangulated in ground-based observations, showing a compact geocentric radiant at RA = 119°9±5°3, Dec = +78°2±0°9, with speed V_{g} = 14.9±0.7 km/s, close to the predicted position. Light curves were U-shaped, with peak luminosity at 88 km altitude, where a wake faded in 1.08±0.17s (1/e). Activity was of relatively long duration (5-h FWHM). It remains unclear when this dust was ejected.
Formation and Evolution of Galaxy Bulges (IAU S245)
NASA Astrophysics Data System (ADS)
Bureau, Martin; Athanassoula, E.; Barbuy, Beatriz
Preface; Organising committee; Symposium photograph; Symposium participants; Part I. Formation and Evolution of Bulges: 1. Bulge models Martin Bureau; 2. Bulges and hierarchical formation Chanda Jog; 3. Bulges and secular evolution Ronald Buta; Part II. Star Formation and Nuclear Activity: 4. Star formation and gaseous flows Joseph Shields; 5. Black holes and nuclear activity Evgeny Polyachenko; Part III. Stellar Populations: 6. Integrated Stellar Populations Maren Hempel; 7. Resolved Stellar Populations Walter Maciel; Part IV. Distant Bulges and Large Surveys: 8. Surveys Jochen Liske; 9. High-z universe Martin Bureau; Author index.
Astrophysical Masers and their Environments (IAU S242)
NASA Astrophysics Data System (ADS)
Chapman, Jessica M.; Baan, Willem A.
Preface; Conference prelims; Tribute to Raymond James Cohen J. M. Chapman and W. A. Baan; History P. Edwards; Session 1. Maser theory Anne Green; Session 2. Polarization and magnetic fields Athol Kemball; Session 3. Masers and star formation Mark Wardle; Session 4. Galactic maser surveys Philip Diamond and Hiroshi Imai; Session 5. Stellar masers, circumstellar winds and supernova remnants Hiroshi Imai, Crystal Brogan and Miller Goss; Session 6. Galactic structure and the Galactic Centre Luis Rodriguez; Session 7. Masers in AGN environments Moshe Elitzur; Session 8. Megamaser and starburst activity Lincoln Greenhill; Session 9. Diagnostics and interpretation in extragalactic environments Colin Lonsdale; Session 10. New millimeter and sub-millimeter masers Indra Bains; Session 11. Future facilities and conference summary Elizabeth Humphreys and Karl Menten; Author index.
Astrophysical Masers and their Environments (IAU S242)
NASA Astrophysics Data System (ADS)
Chapman, Jessica M.; Baan, Willem A.
Preface; Conference prelims; Tribute to Raymond James Cohen J. M. Chapman and W. A. Baan; History P. Edwards; Session 1. Maser theory Anne Green; Session 2. Polarization and magnetic fields Athol Kemball; Session 3. Masers and star formation Mark Wardle; Session 4. Galactic maser surveys Philip Diamond and Hiroshi Imai; Session 5. Stellar masers, circumstellar winds and supernova remnants Hiroshi Imai, Crystal Brogan and Miller Goss; Session 6. Galactic structure and the Galactic Centre Luis Rodriguez; Session 7. Masers in AGN environments Moshe Elitzur; Session 8. Megamaser and starburst activity Lincoln Greenhill; Session 9. Diagnostics and interpretation in extragalactic environments Colin Lonsdale; Session 10. New millimeter and sub-millimeter masers Indra Bains; Session 11. Future facilities and conference summary Elizabeth Humphreys and Karl Menten; Author index.
Dynamics of Populations of Planetary Systems (IAU C197)
NASA Astrophysics Data System (ADS)
Knezevic, Zoran; Milani, Andrea
1. Resonances and stability of extra-solar planetary systems C. Beaugé, N. Callegari, S. Ferraz-Mello and T. A. Michtchenko; 2. Formation, migration, and stability of extrasolar planetary systems Fred C. Adams; 3. Dynamical evolution of extrasolar planetary systems Ji-Lin Zhou and Yi-Sui Sun; 4. Dynamics of planetesimals: the role of two-body relaxation Eiichiro Kokubo; 5. Fitting orbits Andrzej J. Maciejewski, Krzysztof Gozdziewski and Szymon Kozlowski; 6. The secular planetary three body problem revisited Jacques Henrard and Anne-Sophie Libert; 7. Dynamics of extrasolar systems at the 5/2 resonance: application to 47 UMa Dionyssia Psychoyos and John D. Hadjidemetriou; 8. Our solar system as model for exosolar planetary systems Rudolf Dvorak, Áron Süli and Florian Freistetter; 9. Planetary motion in double stars: the influence of the secondary Elke Pilat-Lohinger; 10. Planetary orbits in double stars: influence of the binary's orbital eccentricity Daniel Benest and Robert Gonczi; 11. Astrometric observations of 51 Peg and Gliese 623 at Pulkovo observatory with 65 cm refractor N. A. Shakht; 12. Observations of 61 Cyg at Pulkovo Denis L. Gorshanov, N. A. Shakht, A. A. Kisselev and E. V. Poliakow; 13. Formation of the solar system by instability Evgeny Griv and Michael Gedalin; 14. Behaviour of a two-planetary system on a cosmogonic time-scale Konstantin V. Kholshevnikov and Eduard D. Kuznetsov; 15. Boundaries of the habitable zone: unifying dynamics, astrophysics, and astrobiology Milan M. Cirkovic; 16. Asteroid proper elements: recent computational progress Fernando Roig and Cristian Beaugé; 17. Asteroid family classification from very large catalogues Anne Lemaitre; 18. Non-gravitational perturbations and evolution of the asteroid main belt David Vokrouhlicky, M. Broz and W. F. Bottke, D. Nesvorny and A. Morbidelli; 19. Diffusion in the asteroid belt Harry Varvoglis; 20. Accurate model for the Yarkovsky effect David Capek and David Vokrouhlicky; 21. The population of asteroids in the 2:1 mean motion resonance with Jupiter revised Miroslav Broz, D. Vokrouhlicky, F. Roig, D. Nesvorny, W. F. Bottke and A. Morbidelli; 22. On the reliability of computation of maximum Lyapunov Characteristic Exponents for asteroids Zoran Knezevic and Slobodan Ninkovic; 23. Nekhoroshev stability estimates for different models of the Trojan asteroids Christos Efthymiopoulos; 24. The role of the resonant 'stickiness' in the dynamical evolution of Jupiter family comets A. Alvarez-Canda and F. Roig; 25. Regimes of stability and scaling relations for the removal time in the asteroid belt: a simple kinetic model and numerical tests Mihailo Cubrovic; 26. Virtual asteroids and virtual impactors Andrea Milani; 27. Asteroid population models Alessandro Morbidelli; 28. Linking Very Large Telescope asteroid observations M. Granvik, K. Muinonen, J. Virtanen, M. Delbó, L. Saba, G. De Sanctis, R. Morbidelli, A. Cellino and E. Tedesco; 29. Collision orbits and phase transition for 2004 AS1 at discovery Jenni Virtanen, K. Muinonen, M. Granvik and T. Laakso; 30. The size of collision solutions in orbital elements space G. B. Valsecchi, A. Rossi, A. Milani and S. R. Chesley; 31. Very short arc orbit determination: the case of asteroid 2004 FU162 Steven R. Chesley; 32. Nonlinear impact monitoring: 2-dimensional sampling Giacomo Tommei; 33. Searching for gravity assisted trajectories to accessible near-Earth asteroids Stefan Berinde; 34. KLENOT - Near Earth and other unusual objects observations Michal Kocer, Jana Tichá and M. Tichy; 35. Transport of comets to the Inner Solar System Hans Rickman; 36. Nongravitational Accelerations on Comets Steven R. Chesley and Donald K. Yeomans; 37. Interaction of planetesimals with the giant planets and the shaping of the trans-Neptunian belt Harold F. Levison and Alessandro Morbidelli; 38. Transport of comets to the outer p
Report of the IAU Working Group on Solar Eclipses
NASA Astrophysics Data System (ADS)
Pasachoff, Jay M.
The Working Group on Solar Eclipses coordinates scientists and information in the study of the Sun and the heliosphere at solar eclipses. Our Website at http://eclipses.info has a wide variety of information, including links to maps and other websites dealing with solar eclipses, as well as information on how to observe the partial-phases of solar eclipses safely and why it is interesting for not only scientists but also for the public to observe eclipses and to see how we work to uncover the mysteries of the sun's upper atmosphere. In the last triennium, there were total eclipses in Australia and the Pacific in 2012; in an arc across Africa from Gabon to Uganda and Kenya in 2013; and in the Arctic, including Svalbard and the Faeroes plus many airplanes aloft, in 2015. In the coming triennium, there will be total solar eclipses in Indonesia and the Pacific in 2016 and then, on 21 August 2017, a total solar eclipse that will sweep across the Continental United States from northwest to southeast. Mapping websites, all linked to http://eclipses.info, include Fred Espenak's http://EclipseWise.com; Michael Zeiler's http://GreatAmericanEclipse.com and http://eclipse-maps.com; Xavier Jubier's http://xjubier.free.fr; and (with weather and cloudiness analysis) Jay Anderson's http://eclipser.ca. Members of the Working Group, chaired by Jay Pasachoff (U.S.), include Iraida Kim (Russia), Kiroki Kurokawa (Japan), Jagdev Singh (India), Vojtech Rusin (Slovakia), Zhongquan Qu (China), Fred Espenak (U.S.), Jay Anderson (Canada), Glenn Schneider (U.S.), Michael Gill (U.K.), Xavier Jubier (France), Michael Zeiler (U.S.), and Bill Kramer (U.S.).
Dark Galaxies and Lost Baryons (IAU S244)
NASA Astrophysics Data System (ADS)
Davies, Jonathan I.; Disney, Michael J.
Preface; Conference prelims; The HI that barked in the night M. J. Disney; The detection of dark galaxies in blind HI surveys J. I. Davies; Red haloes of galaxies - reservoirs of baryonic dark matter? E. Zackrisson, N. Bergvall, C. Flynn, G. Ostlin, G. Micheva and B. Baldwell; Constraints on dark and visible mass in galaxies from strong gravitational lensing S. Dye and S. Warren; Lost baryons at low redshift S. Mathur, F. Nicastro and R. Williams; Observed properties of dark matter on small spatial scales R. Wyse and G. Gilmore; The mass distribution in spiral galaxies P. Salucci; Connecting lost baryons and dark galaxies via QSO absorption lines T. Tripp; ALFALFA: HI cosmology in the local universe R. Giovanelli; The ALFALFA search for (almost) dark galaxies across the HI mass function M. Haynes; HI clouds detected towards Virgo with the Arecibo Legacy Fast ALFA Survey B. Kent; Cosmic variance in the HI mass function S. Schneider; The Arecibo Galaxy Environments Survey - potential for finding dark galaxies and results so far R. Minchin et al.; Free-floating HI clouds in the M81 group E. Brinks, F. Walter and E. Skillman; Where are the stars in dark galaxies J. Rosenberg, J. Salzer and J. Cannon; The halo by halo missing baryon problem S. McGaugh; The local void is really empty R. Tully; Voids in the local volume: a limit on appearance of a galaxy in a dark matter halo A. Tikhonov and A. Klypin; Dim baryons in the cosmic web C. Impey; A census of baryons in galaxy clusters and groups A. Gonzalez, D. Zaritsky and A. Zabludo; Statistical properties of the intercluster light from SDSS image stacking S. Zibetti; QSO strong gravitational lensing and the detection of dark halos A. Maccio; Strong gravitational lensing: bright galaxies and lost dark-matter L. Koopmans; Mapping the distribution of luminous and dark matter in strong lensing galaxies I. Ferreras, P. Saha, L. Williams and S. Burles; Tidal debris posing as dark galaxies P. Duc, F. Bournaud and E. Brinks; Numerical simulation of the dwarf companions of giant galaxies A. Nelson and P. Williams; Delayed galaxies C. Struck, M. Hancock, B. Smith, P. Appleton, V. Charmandaris and M. Giroux; Probe of dark galaxies via disturbed/lopsided isolated galaxies I. Karachentsev, V. Karachentseva, W. Huchtmeier, D. Makarov and S. Kaisin; Star formation thresholds J. Schaye; Scaling relations of dwarf galaxies without supernova-driven winds K. Tassis, A. Kravtsov and N. Gnedin; Star formation in massive low surface brightness galaxies K. O'Neil; Linking clustering properties and the evolution of low surface brightness galaxies D. Bomans and S. Rosenbaum; Too small to form a galaxy: how the UV background determines the baryon fraction M. Hoeft, G. Yepes and S. Gottlober; Star formation in damped Lyman selected galaxies L. Christensen; Dark-matter content of early-type galaxies with planetary nebulae N. Napolitano et al.; Hunting for ghosts: low surface brightnesses from pixels R. Scaramella and S. Sabatini; Baryonic properties of the darkest galaxies E. Grebel; The dwarf low surface brightness population in different environments of the local universe S. Sabatini, J. Davies, S. Roberts and R. Scaramella; Mass modelling of dwarf spheroidal galaxies J. Klimentowski et al.; Evolution of dwarf galaxies in the Centaurus A Group L. Makarova and D. Makarov; A flat faint end of the Fornax cluster galaxy luminosity function S. Mieske, M. Hilker, L. Infante and C. Mendes de Oliveira; Can massive dark halos destroy the discs of dwarf galaxies? B. Fuchs and O. Esquivel; 'Dark galaxies' and local very metal-poor gas-rich galaxies: possible interrelations S. Pustilnik; Morphology and environment of dwarf galaxies in the local universe H. Ann; Arecibo survey of HI emission from disk galaxies at redshift z 0.2 B. Catinella, M. Haynes, J. Gardner, A. Connolly and R. Giovanelli; AGES observations of
Low-metallicity Star Formation (IAU S255)
NASA Astrophysics Data System (ADS)
Hunt, Leslie K.; Madden, Suzanne C.; Schneider, Raffaella
Preface; SOC and LOC; Participants; Life at the conference; Conference photo; Session I. Population III and Metal-Free Star Formation: 1. Open questions in the study of population III star formation S. C. O. Glover, P. C. Clark, T. H. Greif, J. L. Johnson, V. Bromm, R. S. Klessen and A. Stacy; 2. Protostar formation in the early universe Naoki Yoshida; 3. Population III.1 stars: formation, feedback and evolution of the IMF Jonathan C. Tan; 4. The formation of the first galaxies and the transition to low-mass star formation T. H. Greif, D. R. G. Schleicher, J. L. Johnson, A.-K. Jappsen, R. S. Klessen, P. C. Clark, S. C. O. Glover, A. Stacy and V. Bromm; 5. Low-metallicity star formation: the characteristic mass and upper mass limit Kazuyuki Omukai; 6. Dark stars: dark matter in the first stars leads to a new phase of stellar evolution Katherine Freese, Douglas Spolyar, Anthony Aguirre, Peter Bodenheimer, Paolo Gondolo, J. A. Sellwood and Naoki Yoshida; 7. Effects of dark matter annihilation on the first stars F. Iocco, A. Bressan, E. Ripamonti, R. Schneider, A. Ferrara and P. Marigo; 8. Searching for Pop III stars and galaxies at high redshift Daniel Schaerer; 9. The search for population III stars Sperello di Serego Alighieri, Jaron Kurk, Benedetta Ciardi, Andrea Cimatti, Emanuele Daddi and Andrea Ferrara; 10. Observational search for population III stars in high-redshift galaxies Tohru Nagao; Session II. Metal Enrichment, Chemical Evolution, and Feedback: 11. Cosmic metal enrichment Andrea Ferrara; 12. Insights into the origin of the galaxy mass-metallicity relation Henry Lee, Eric F. Bell and Rachel S. Somerville; 13. LSD and AMAZE: the mass-metallicity relation at z > 3 F. Mannucci and R. Maiolino; 14. Three modes of metal-enriched star formation at high redshift Britton D. Smith, Matthew J. Turk, Steinn Sigurdsson, Brian W. O'Shea and Michael L. Norman; 15. Primordial supernovae and the assembly of the first galaxies Daniel Whalen, Bob Van Veelen, Brian W. O'Shea and Michael L. Norman; 16. Damped Lyα systems as probes of chemical evolution over cosmological timescales Miroslava Dessauges-Zavadsky; 17. Connecting high-redshift galaxy populations through observations of local damped Lyman alpha dwarf galaxies Regina E. Schulte-Ladbeck; 18. Chemical enrichment and feedback in low metallicity environments: constraints on galaxy formation Francesca Matteucci; 19. Effects of reionization on dwarf galaxy formation Massimo Ricotti; 20. The importance of following the evolution of the dust in galaxies on their SEDs A. Schurer, F. Calura, L. Silva, A. Pipino, G. L. Granato, F. Matteucci and R. Maiolino; 21. About the chemical evolution of dSphs (and the peculiar globular cluster ωCen) Andrea Marcolini and Annibale D'Ercole; 22. Young star clusters in the small Magellanic cloud: impact of local and global conditions on star formation Elena Sabbi, Linda J. Smith, Lynn R. Carlson, Antonella Nota, Monca Tosi, Michele Cignoni, Jay S. Gallagher III, Marco Sirianni and Margaret Meixner; 23. Modeling the ISM properties of metal-poor galaxies and gamma-ray burst hosts Emily M. Levesque, Lisa J. Kewley, Kirsten Larson and Leonie Snijders; 24. Dwarf galaxies and the magnetisation of the IGM Uli Klein; Session III. Explosive Events in Low-Metallicity Environments: 25. Supernovae and their evolution in a low metallicity ISM Roger A. Chevalier; 26. First stars - type Ib supernovae connection Ken'ichi Nomoto, Masaomi Tanaka, Yasuomi Kamiya, Nozomu Tominaga and Keiichi Maeda; 27. Supernova nucleosynthesis in the early universe Nozomu Tominaga, Hideyuki Umeda, Keiichi Maeda, Ken'ichi Nomoto and Nobuyuki Iwamoto; 28. Powerful explosions at Z = 0? Sylvia Ekström, Georges Meynet, Raphael Hirschi and André Maeder; 29. Wind anisotropy and stellar evolution Cyril Georgy, Georges Meynet and André Maeder; 30. Low-mass and metal-poor gamma-ray burst
Multiwavelength AGN Surveys and Studies (IAU S304)
NASA Astrophysics Data System (ADS)
Mickaelian, Areg M.; Sanders, David B.
1. Historical surveys: spectral and colorimetric surveys for AGN, surveys for UV-excess galaxies; 2. AGN from IR/submm surveys: 2MASS, IRAS, ISO, AKARI, SCUBA, SST, WISE, Herschel; 3. AGN from radio/mm surveys: NVSS, FIRST, ALMA, Planck, and others; 4. AGN from X-ray/gamma-ray surveys: ROSAT, ASCA, BeppoSAX, Chandra, XMM, INTEGRAL, Fermi, HESS, MAGIC, VERITAS, NuSTAR; 5. Multiwavelength AGN surveys, AGN statistics and cross-correlation of multiwavelength surveys; 6. Unification and other models of AGN, accretion modes, understanding of the structure of nearby AGN from IFUs on VLT and other telescopes; 7. AGN feedback in galaxies and clusters, AGN host galaxies and the AGN environments; 8. Binary AGN and Merging Super-Massive Black Holes; 9. Study of unique AGN, AGN variability and the Phenomena of Activity; 10. Future large projects; Author index.
IAU nomenclature for albedo features on the planet Mercury
NASA Technical Reports Server (NTRS)
Dollfus, A.; Chapman, C. R.; Davies, M. E.; Gingerich, O.; Goldstein, R.; Guest, J.; Morrison, D.; Smith, B. A.
The International Astronomical Union has endorsed a nomenclature for the albedo features on Mercury. Designations are based upon the mythological names related to the god Hermes; they are expressed in Latin form. The dark-hued albedo features are associated with the generic term Solitudo. The light-hued areas are designated by a single name without generic term. The 32 names adopted are allocated on the Mercury map.
Discovery of the February Epsilon Virginids (FEV, IAU#506)
NASA Astrophysics Data System (ADS)
Steakley, Kathryn; Jenniskens, P. M.
Halley type comets are relatively few, but at Earth they are sampled over a large part of the inner solar system because dust accumulates in comparatively stable orbits. We have detected a new meteor shower with a Halley-type orbit, the February epsilon Virginids (FEV), from video observations with the Cameras for All-Sky Meteor Surveillance (CAMS) and by examining orbits listed in the SonataCo Japanese database. Twenty-two meteors were detected during the period from February 1st through February 9th of 2008 to 2012 that are part of this shower. The FEVs originate from the geocentric radiant of R.A. = 201.66° and Dec = +10.39° with a mean geocentric velocity of 63.01 km/s. The mean orbital elements of these meteoroids are q = (0.488 ± 0.021) AU, 1/a = ( 0.085 ± 0.095) 1/AU, e = 0.958 ± 0.046, i = 138.05° ± 1.28°, ω = 271.15° ± 3.70°, Ω = 315.26 ± 0.86°, and Π = 228.12°. We investigated whether this meteoroid stream could have originated from comets C/1978 T3 (Bradfield), C/1808 F1 (Pons), or C/1939 H1 (Jurlof-Achmarof-Hassel). If the parent body can be identified, we can determine when the comet was first captured into a low perihelion distance orbit. Future examination of the shower will allow us to examine the physical properties of the parent comet.
Origins of magnetospheric plasma
Moore, T.E. )
A review is given of recent (1987-1990) progress in understanding of the origins of plasmas in the earth's magnetosphere. In counterpoint to the early supposition that geomagnetic phenomena are produced by energetic plasmas of solar origin, 1987 saw the publication of a provocative argument that accelerated ionospheric plasma could supply all magnetospheric auroral and ring current particles. Significant new developments of existing data sets, as well as the establishment of entirely new data sets, have improved the ability to identify plasma source regions and to track plasma through the magnetospheric system of boundary layers and reservoirs. These developments suggest that the boundary between ionospheric and solar plasmas, once taken to lie at the plasmapause, actually lies much nearer to the magnetopause. Defining this boundary as the surface where solar wind and ionosphere contribute equally to the plasma, it is referred to herein as the 'geopause'. It is now well established that the infusion of ionospheric O(+) plays a major role in the storm-time distention of the magnetotail and inflation of the inner magnetosphere. After more than two decades of observation and debate, the question remains whether magnetosheric are protons of solar or terrestrial origin. 161 refs.
Plasma stabilization experiment
NASA Astrophysics Data System (ADS)
Sziklas, E. A.; Fader, W. J.; Jong, R. A.; Stufflebeam, J. H.
The plasma stabilization experiment is an effort to enhance stability in a mirror-confined plasma by trapping cold ions with rf fields applied near the mirror throats. Nagoya Type 3 antennas, coupled to a 60 kW rf power supply are mounted in the throats of the UTRC baseball magnet. An external washer gun provides a source of plasma for both streaming and confined plasma tests. Results show a strong stoppering effect on streaming plasmas and a marginal effect on confined plasmas. Theoretical calculations provide an explanation for the experimental observations. The field generates a ponderomotive force acting on the electrons. The resultant improvement in electron confinement changes the ambipolar potential and inhibits the flow of ions through the mirror throat. Criteria are derived for the validity of this trapping concept. The requisite field strengths are significantly lower than those required to trap ions directly. Scaling laws are developed for application of cold ion trapping to large mirror devices containing dense plasmas. The use of slow-wave antenna structures operated at frequencies above the lower hybrid frequency is recommended for these applications.
High energy plasma accelerators
Tajima, T.
Colinear intense laser beams ..omega../sub 0/, kappa/sub 0/ and ..omega../sub 1/, kappa/sub 1/ shone on a plasma with frequency separation equal to the electron plasma frequency ..omega../sub pe/ are capable of creating a coherent large longitudinal electric field E/sub L/ = mc ..omega../sub pe//e of the order of 1GeV/cm for a plasma density of 10/sup 18/ cm/sup -3/ through the laser beat excitation of plasma oscillations. Accompanying favorable and deleterious physical effects using this process for a high energy beat-wave accelerator are discussed: the longitudinal dephasing, pump depletion, the transverse laser diffraction, plasma turbulence effects, self-steepening, self-focusing, etc. The basic equation, the driven nonlinear Schroedinger equation, is derived to describe this system. Advanced accelerator concepts to overcome some of these problems are proposed, including the plasma fiber accelerator of various variations. An advanced laser architecture suitable for the beat-wave accelerator is suggested. Accelerator physics issues such as the luminosity are discussed. Applications of the present process to the current drive in a plasma and to the excitation of collective oscillations within nuclei are also discussed.
Dense Hypervelocity Plasma Jets
NASA Astrophysics Data System (ADS)
Case, Andrew; Witherspoon, F. Douglas; Messer, Sarah; Bomgardner, Richard; Phillips, Michael; van Doren, David; Elton, Raymond; Uzun-Kaymak, Ilker
We are developing high velocity dense plasma jets for fusion and HEDP applications. Traditional coaxial plasma accelerators suffer from the blow-by instability which limits the mass accelerated to high velocity. In the current design blow-by is delayed by a combination of electrode shaping and use of a tailored plasma armature created by injection of a high density plasma at a few eV generated by arrays of capillary discharges or sparkgaps. Experimental data will be presented for a complete 32 injector gun system built for driving rotation in the Maryland MCX experiment, including data on penetration of the plasma jet through a magnetic field. We present spectroscopic measurements of plasma velocity, temperature, and density, as well as total momentum measured using a ballistic pendulum. Measurements are in agreement with each other and with time of flight data from photodiodes and a multichannel PMT. Plasma density is above 10^15 cm-3, velocities range up to about 100 km/s. Preliminary results from a quadrature heterodyne HeNe interferometer are consistent with these results.
Erhard Weigel - 1625 to 1699. Baroque patriarch of the early German Enlightenment. Proceedings of the colloquium held in Jena on March 20, 1999, on the occasion of the 300th anniversary of his death (German Title: Erhard Weigel - 1625 bis 1699. Barocker Erzvater der deutschen Frühaufklärung. Beiträge des Kolloquium anlässlich seines 300. Todestages am 20. März 1999 in Jena)
NASA Astrophysics Data System (ADS)
Schielicke, Reinhard E.; Herbst, Klaus-Dieter; Kratchowil, Stefan
Erhard Weigel was Professor of Mathematics at Jena University between 1653 and 1699. He has got a place in the history of science thanks to his mathematical and astronomical knowledge, which he was able to demonstrate also in popular forms, his numerous inventions, his pedagogical enterprises, as well as his engagement for the Gregorian reform of the calender in the protestantic states, connected with the foundation of a scientific academy. This volumes contains a review article, followed by seven contributions with latest results of investigations about Weigel, presented at a colloquium held in Jena on the occasion of the 300th anniversary of his death.
Plasma control and utilization
Ensley, Donald L.
A plasma is confined and heated by a microwave field resonant in a cavity excited in a combination of the TE and TM modes while responding to the resonant frequency of the cavity as the plasma dimensions change to maintain operation at resonance. The microwave field is elliptically or circularly polarized as to prevent the electromagnetic confining field from going to zero. A high Q chamber having superconductive walls is employed to minimize wall losses while providing for extraction of thermonuclear energy produced by fusion of nuclei in the plasma.
NASA Astrophysics Data System (ADS)
Keidar, Michael
Plasma medicine is a relatively new field that grew from research in application of low-temperature (or cold) atmospheric plasmas in bioengineering. One of the most promising applications of cold atmospheric plasma (CAP) is cancer therapy. Convincing evidence of CAP selectivity towards the cancer cells has been accumulated. This review summarizes the state of the art of this emerging field, presenting various aspects of CAP application in cancer such as the role of reactive species (reactive oxygen and nitrogen), cell cycle modification, in vivo application, CAP interaction with cancer cells in conjunction with nanoparticles, and computational oncology applied to CAP.
NASA Technical Reports Server (NTRS)
Calvert, W.
A region of diminished plasma density has been found to occur at the source of auroral kilometric radiation (AKR). The density within this auroral plasma cavity, determined from limited Hawkeye wave data, was less than 1/cu cm from 1.8 to 3 earth radii geocentric, at 70 deg + or - 3 deg invariant magnetic latitude. The altitude variation of the magnetic field produces a minimum in the ratio of plasma frequency to cyclotron frequency within the cavity which accounts for the observed spectrum of AKR.
Killian, Thomas C
Ultracold neutral plasmas occupy an exotic regime of plasma physics in which electrons form a swarming, neutralizing background for ions that sluggishly move in a correlated manner. Strong interactions between the charged particles give rise to surprising dynamics such as oscillations of the average kinetic energy during equilibration and extremely fast recombination. Such phenomena offer stimulating and challenging problems for computational scientists, and the physics can be applied to other environments, such as the interior of gas giant planets and plasmas created by short-pulse laser irradiation of solid, liquid, and cluster targets. PMID:17478712
Thermal plasmas for nanofabrication
NASA Astrophysics Data System (ADS)
Shigeta, Masaya; Murphy, Anthony B.
In this paper, we review the recent progress in nanofabrication by thermal plasmas, and attempt to define some of the most important issues in the field. For synthesis of nanoparticles, the experimental studies in the past five years are briefly introduced; the theoretical and numerical modelling works of the past 20 years are reviewed with some detailed explanations. Also, the use of thermal plasmas to produce nanostructured films and coatings is described. A wide range of technologies have been developed, ranging from chemical vapour deposition processes to new plasma spraying processes. We present an overview of the different techniques and the important physical phenomena, as well as the requirements for future progress.
Davies, I. J. T.; Musa, M.; Dormandy, T. L.
Zinc is an essential trace element. Previous methods of measuring zinc in clinical material have been difficult and reported findings must be treated with caution. Using atomic absorption spectroscopy it has been established that plasma zinc is one of the most uniform biochemical characteristics of normal adult blood. Sex and age differences in adult life are insignificant. Increased metabolic activity, on the other hand, induces a marked, immediate fall in plasma zinc level. The possible implications of this are discussed. Zinc levels in patients with diabetes mellitus, cardiovascular disease, and anaemia due to acute blood loss have been within normal limits. Plasma zinc is low in certain types of liver disease. PMID:5303355
NASA Technical Reports Server (NTRS)
Gallagher, Dennis L.; Craven, P. D.; Comfort, R. H.
Abstract. The Global Core Plasma Model (GCPM) provides, empirically derived, core plasma density as a function of geomagnetic and solar conditions throughout the inner magnetosphere. It is continuous in value and gradient and is composed of separate models for the ionosphere, the plasmasphere, the plasmapause, the trough, and the polar cap. The relative composition of plasmaspheric H+, He+, and O+ is included in the GCPM. A blunt plasmaspheric bulge and rotation of the bulge with changing geomagnetic conditions is included. The GCPM is an amalgam of density models, intended to serve as a framework for continued improvement as new measurements become available and are used to characterize core plasma density, composition, and temperature.
Neutral Gas Plasma Interactions in Space Plasma
NASA Astrophysics Data System (ADS)
Liou, Kan
A sounding rocket experiment, CRIT-II, involving the injection of shaped-charge barium in ionospheric plasma was conducted on May 7, 1989, to investigate Alfven's critical ionization velocity (CIV) hypothesis in space. The CRIT -II main payload was instrumented to make in situ measurements within the neutral barium beam. Among the detectors, UNH provided three energetic particle detectors and two photometers. The data from these detectors are presented. The typical features of the CIV effect were observed including plasma density enhancement, energy and momentum loss of a fast ion beam, excitation of plasma waves, and electron heating. It was found by optical observations that about 4% of the neutral barium was ionized. We believe that about one half of these barium ions were created by electron impact ionization --a CIV mechanism. The cross section for collisions between the barium atoms and the ionospheric oxygen ions was also calculated, assuming that the other half of ionizing barium ions were mainly generated by charge exchange, and found to be in the range from 1 times 10 ^{-17} cm^{-2} at a velocity of 4 km/s to 1 times 10^{-15} cm^{-2} at a velocity of 20 km/s. We also confirmed that the early observed ions were originally from the collisionally accelerated neutral oxygen which charge exchanges with the local oxygen ions. The early stage of electron heating was confirmed to be the result of lower hybrid instabilities excited by the precursor ion beam, using our quasi-linear model calculation. However, the wave spectrum during the passage of main streaming barium was found to be inconsistent with the lower hybrid instabilities proposed by current CIV theories. This could be the main reason for a relatively low ionization yield that one otherwise would expect from CRIT-II. A multi-fluid model of the wave dispersion relation for an unmagnetized beam with finite width in a magnetized plasma was also derived. We found that the nonuniform beam density effect
Plasma Chemical Aspects Of Dust Formation In Hydrocarbon Plasmas
Berndt, J.; Kovacevic, E.; Stepanovic, O.; Stefanovic, I.; Winter, J.
This contribution deals with some plasma chemical aspects of dust formation in hydrocarbon plasmas. The interplay between dust formation and plasma chemistry will be discussed by means of different experimental results. One specific example concerns the formation of benzene and the role of atomic hydrogen for plasma chemical processes and dust formation in hydrocarbon discharges.
SOLERS22 Working Group 1 Report
NASA Technical Reports Server (NTRS)
Pap, Judit M.; Wehrli, Christoph
SOLERS22 Working Group 1 had extensive discussions of current and future space and ground-based observations of total solar irradiance as well as near-UV, visible, and infrared irradiances during the 1-day SOLERS22 meeting held at the IAU Colloquium No. 143 on June 25, 1993. The list of WG1 members attending this session is given at the end of this report.
Arc plasma jets of a nontransferred plasma torch
Kang, K.D.; Hong, S.H.
The dc plasma torches have been widely used as clean plasma sources for plasma processings such as plasma spraying and synthesis. The plasma flow of a nontransferred plasma torch used for thermal plasma processings is produced by the arc-gas interactions between a cathode tip and an anode nozzle and expands as a jet through the nozzle. In this work, numerically calculated images of the arc plasma characteristics are found over the entire plasma region, including both an arc-gas interacting region inside the torch and a jet expanding region outside the torch. A numerical model used assumes a local thermodynamic equilibrium (LTE) with near-electrode phenomena and compressible flow effects. The computational system is described by a two-dimensional (2-D) axisymmetric model which is solved for plasma temperature and velocity by a control volume approach with the modified SIMPLER algorithm in a real torch geometry.
Holland, Chris [UC San Diego, San Diego, California, United States
The upcoming ITER experiment (www.iter.org) represents the next major milestone in realizing the promise of using nuclear fusion as a commercial energy source, by moving into the ?burning plasma? regime where the dominant heat source is the internal fusion reactions. As part of its support for the ITER mission, the US fusion community is actively developing validated predictive models of the behavior of magnetically confined plasmas. In this talk, I will describe how the plasma community is using the latest high performance computing facilities to develop and refine our models of the nonlinear, multiscale plasma dynamics, and how recent advances in experimental diagnostics are allowing us to directly test and validate these models at an unprecedented level.
Saturn's Hot Plasma Explosions
This animation based on data obtained by NASA's Cassini Spacecraft shows how the "explosions" of hot plasma on the night side (orange and white) periodically inflate Saturn's magnetic field (white ...
Hull, D.E.
An induction plasma tube having a segmented, fluid-cooled internal radiation shield is disclosed. The individual segments are thick in cross-section such that the shield occupies a substantial fraction of the internal volume of the plasma enclosure, resulting in improved performance and higher sustainable plasma temperatures. The individual segments of the shield are preferably cooled by means of a counterflow fluid cooling system wherein each segment includes a central bore and a fluid supply tube extending into the bore. The counterflow cooling system results in improved cooling of the individual segments and also permits use of relatively larger shield segments which permit improved electromagnetic coupling between the induction coil and a plasma located inside the shield. Four embodiments of the invention, each having particular advantages, are disclosed.
Hull, Donald E.
An induction plasma tube having a segmented, fluid-cooled internal radiation shield is disclosed. The individual segments are thick in cross-section such that the shield occupies a substantial fraction of the internal volume of the plasma enclosure, resulting in improved performance and higher sustainable plasma temperatures. The individual segments of the shield are preferably cooled by means of a counterflow fluid cooling system wherein each segment includes a central bore and a fluid supply tube extending into the bore. The counterflow cooling system results in improved cooling of the individual segments and also permits use of relatively larger shield segments which permit improved electromagnetic coupling between the induction coil and a plasma located inside the shield. Four embodiments of the invention, each having particular advantages, are disclosed.
Frank, A.M.
This paper describes a technique by which the sensitivity of plasma interferometers can be increased. Stabilization and fractional fringe measurement techniques have improved to the point where additional optical sensitivity could be useful. (MOW)
Accelerating Particles with Plasma
Litos, Michael; Hogan, Mark
Researchers at SLAC explain how they use plasma wakefields to accelerate bunches of electrons to very high energies over only a short distance. Their experiments offer a possible path for the future of particle accelerators.
NASA Astrophysics Data System (ADS)
Mauk, Barry H.
Magnetospheric Plasma Physics is volume 4 of an ongoing series of review books entitled Developments in Earth and Planetary Sciences organized by the Center for Academic Publications Japan. The series is intended to stress Japanese work; however, the present volume was written by seven internationally selected authors who have reviewed works from a broad range of sources. This volume is composed of articles drawn from five lecture series presented at the Autumn College o f Plasma Physics, International Center for Theoretical Physics, Trieste, Italy, October-November 1979. The audiences for these lecture series were plasma and/or space plasma physicists, or students of the same, and the level and tone of this volume clearly reflect that condition.
Wakes in inhomogeneous plasmas.
Kompaneets, Roman; Ivlev, Alexei V; Nosenko, Vladimir; Morfill, Gregor E
The Debye shielding of a charge immersed in a flowing plasma is an old classic problem. It has been given renewed attention in the last two decades in view of experiments with complex plasmas, where charged dust particles are often levitated in a region with strong ion flow. Efforts to describe the shielding of the dust particles in such conditions have been focused on the homogeneous plasma approximation, which ignores the substantial inhomogeneity of the levitation region. We address the role of the plasma inhomogeneity by rigorously calculating the point charge potential in the collisionless Bohm sheath. We demonstrate that the inhomogeneity can dramatically modify the wake, making it nonoscillatory and weaker. PMID:24827356
Hull, D.E.
An induction plasma tube having a segmented, fluid-cooled internal radiation shield is disclosed. The individual segments are thick in cross-section such that the shield occupies a substantial fraction of the internal volume of the plasma enclosure, resulting in improved performance and higher sustainable plasma temperatures. The individual segments of the shield are preferably cooled by means of a counterflow fluid cooling system wherein each segment includes a central bore and a fluid supply tube extending into the bore. The counterflow cooling system results in improved cooling of the individual segments and also permits use of relatively larger shield segments which permit improved electromagnetic coupling between the induction coil and a plasma located inside the shield. Four embodiments of the invention, each having particular advantages, are disclosed.
Measuring the Plasma Density of a Ferroelectric Plasma Source in an Expanding Plasma
A. Dunaevsky; N.J. Fisch
The initial density and electron temperature at the surface of a ferroelectric plasma source were deduced from floating probe measurements in an expanding plasma. The method exploits negative charging of the floating probe capacitance by fast flows before the expanding plasma reaches the probe. The temporal profiles of the plasma density can be obtained from the voltage traces of the discharge of the charged probe capacitance by the ion current from the expanding plasma. The temporal profiles of the plasma density, at two different distances from the surface of the ferroelectric plasma source, could be further fitted by using the density profiles for the expanding plasma. This gives the initial values of the plasma density and electron temperature at the surface. The method could be useful for any pulsed discharge, which is accompanied by considerable electromagnetic noise, if the initial plasma parameters might be deduced from measurements in expanding plasma.
NASA Astrophysics Data System (ADS)
Riemann, Karl-Ulrich
In typical gas discharges a quasineutral plasma is shielded from a negativ absorbing wall by a thin positive sheath that is nearly planar and collision-free. The subdivision of ``plasma'' and ``sheath'' was introduced by Langmuir and is based on a small ratio of the electron Debye lenghth λD to the dominant competing characteristic plasma length l. Depending on the special conditions, l may represent, e.g., the plasma extension, the ionization length, the ion mean free path, the ion gyro radius, or a geometric length. Strictly speaking, this subdivion is possible only in the asymptotic limit λD/l->0. The asymptotic analysis results in singularities at the ``sheath edge'' closely related to the ``Bohm criterion.'' Due to these singularities a direct smooth matching of the separate plasma and sheath soltions is not possible. To obtain a consistent smooth transition, the singular sheath edge must be bridged by an additinal narrow ``intermediate'' model zone accounting both for plasma processes (e.g., collisions) and for the first build up of space charge. Due to this complexity and to different interpretations of the ``classical'' papers by Langmuir and Bohm, the asymptotic plasma-sheath concept and the definition of the sheath edge were questioned and resulted in controversies during the last two decades. We discuss attempts to re-define the sheath edge, to account for finite values of λD/l in the Bohm criterion, and demonstrate the consistent matching of plasma and sheath. The investigations of the plasma-sheath transition discussed so far are based on a simplified fluid analysis that cannot account for the essential inhomogeneity of the boundary layer and for the dominant role of slow ions in space charge formation. Therefore we give special emphasis to the kinetic theory of the plasma-sheath transition. Unfortunately this approach results in an additional mathematical difficulty caused by ions with zero velocity. We discuss attempts to avoid this singularity by
NASA Astrophysics Data System (ADS)
Shohet, J. L.
Plasma-aided manufacturing is used for producing new materials with unusual and superior properties, for developing new chemical compounds and processes, for machining, and for altering and refining materials and surfaces. Plasma-aided manufacturing has direct applications to semiconductor fabrication, materials synthesis, welding, lighting, polymers, anti-corrosion coatings, machine tools, metallurgy, electrical and electronics devices, hazardous waste removal, high performance ceramics, and many other items in both the high-technology and the more traditional industries in the United States.
Plasmas in Saturn's magnetosphere
NASA Technical Reports Server (NTRS)
Frank, L. A.; Burek, B. G.; Ackerson, K. L.; Wolfe, J. H.; Mihalov, J. D.
The solar wind plasma analyzer on board Pioneer 2 provides first observations of low-energy positive ions in the magnetosphere of Saturn. Measurable intensities of ions within the energy-per-unit charge (E/Q) range 100 eV to 8 keV are present over the planetocentric radial distance range about 4 to 16 R sub S in the dayside magnetosphere. The plasmas are found to be rigidly corotating with the planet out to distances of at least 10 R sub S. At radial distances beyond 10 R sub S, the bulk flows appear to be in the corotation direction but with lesser speeds than those expected from rigid corotation. At radial distances beyond the orbit of Rhea at 8.8 R sub S, the dominant ions are most likely protons and the corresponding typical densities and temperatures are 0.5/cu cm and 1,000,000 K, respectively, with substantial fluctuations. It is concluded that the most likely source of these plasmas in the photodissociation of water frost on the surface of the ring material with subsequent ionization of the products and radially outward diffusion. The presence of this plasma torus is expected to have a large influence on the dynamics of Saturn's magnetosphere since the pressure ratio beta of these plasmas approaches unity at radial distances as close to the planet as 6.5 R sub S. On the basis of these observational evidences it is anticipated that quasi-periodic outward flows of plasma, accompanied with a reconfiguration of the magnetosphere beyond about 6.5 R sub S, will occur in the local night sector in order to relieve the plasma pressure from accretion of plasma from the rings.
Electrostatics of moving plasma
Ignatov, A. M.
The stability of charge distribution over the surface of a conducting body in moving plasma is analyzed. Using a finite-width plate streamlined by a cold neutralized electron flow as an example, it is shown that an electrically neutral body can be unstable against the development of spontaneous polarization. The plasma parameters at which such instability takes place, as well as the frequency and growth rate of the fundamental mode of instability, are determined.
Eakle, Robert F.; Pak, Donald J.
A mounting system for a flat display screen, particularly a plasma display screen, suspends the screen separately in each of the x-, y- and z-directions. A series of frames located by linear bearings and isolated by springs and dampers allows separate controlled movement in each axis. The system enables the use of relatively larger display screens in vehicles in which plasma screen are subject to damage from vibration.
Plasma-based accelerator structures
Schroeder, Carl B.
Plasma-based accelerators have the ability to sustain extremely large accelerating gradients, with possible high-energy physics applications. This dissertation further develops the theory of plasma-based accelerators by addressing three topics: the performance of a hollow plasma channel as an accelerating structure, the generation of ultrashort electron bunches, and the propagation of laser pulses is underdense plasmas.
Inductively coupled helium plasma torch
Montaser, Akbar; Chan, Shi-Kit; Van Hoven, Raymond L.
An inductively coupled plasma torch including a base member, a plasma tube and a threaded insert member within the plasma tube for directing the plasma gas in a tangential flow pattern. The design of the torch eliminates the need for a separate coolant gas tube. The torch can be readily assembled and disassembled with a high degree of alignment accuracy.
Plasma surface modification of polymers
NASA Technical Reports Server (NTRS)
Hirotsu, T.
Thin plasma polymerization films are discussed from the viewpoint of simplicity in production stages. The application of selective, absorbent films and films used in selective permeability was tested. The types of surface modification of polymers discussed are: (1) plasma etching, (2) surface coating by plasma polymerized thin films, and (3) plasma activation surface graft polymerization.
Plasma contactor research - 1991
NASA Technical Reports Server (NTRS)
Buchholtz, Brett; Williams, John D.; Wilbur, Paul J.
A report describing the operating principles of hollow-cathode-based plasma contactors emitting or collecting electrons from an ambient plasma is summarized. Preliminary experiments conducted to determine the noise generated by these plasma contactors in the emission-current return line and in the plasma near it are described. These noise data are measured as current fluctuations in the return line and to the Langmuir probe and then analyzed using a fast Fourier transform technique. The spectral compositions of the data are characterized using power spectral density plots which are examined to identify possible noise source(s) and production mechanism(s). The precautions taken in the construction and calibration of the instrumentation to assure adequate frequency response are described. Experimental results show that line-current noise levels are typically 2 percent of the electron current being emitted or collected. However, noise levels increase to as much as 20 percent of the electron current at a few electron-collection operating conditions. The frequencies associated with most of the noise were harmonics of the 60 Hz input to system power supplies. Plasma noise had characteristics similar in magnitude and frequency to those for the return-line noise, but they contained additional features at frequencies considered to be related to ion-acoustic instabilities. Also discussed is a new probe positioning system built to facilitate future plasma-contractor research.
Ferromagnetic enhanced inductive plasma sources
NASA Astrophysics Data System (ADS)
Godyak, Valery
The subject of this paper is the review of inductively coupled plasma (ICP) sources enhanced with ferromagnetic cores, FMICP, found in various applications, including plasma fusion, space propulsion, light sources, plasma chemistry and plasma processing of materials. The history of FMICP, early attempts for their realization, some recent developments and examples of successful FMICP devices are given here. A comparative study of FMICPs with conventional ICPs demonstrates their certain advantages in power transfer efficiency, power factor and their ability to operate without rf plasma potentials at low plasma densities and with small gaps, while effectively controlling plasma density profile.
Tarey, R. D.; Sahu, B. B.; Ganguli, A.
This paper presents a comprehensive overview of work on the helicon plasmas and also discusses various aspects of RF power deposition in such plasmas. Some of the work presented here is a review of earlier work on theoretical [A. Ganguli et al., Phys. Plasmas 14, 113503 (2007)] and experimental [A. Ganguli et al., Plasma Sources Sci. Technol. 20(1), 015021 (2011)] investigations on helicon plasmas in a conducting cylindrical waveguide for m = -1 mode. This work also presents an approach to investigate the mechanisms by which the helicon and associated Trivelpiece-Gould (TG) waves are responsible for RF power deposition in Helicon discharges. Experiment design adopts the recent theory of damping and absorption of Helicon modes in conducting waveguides [A. Ganguli et al., Phys. Plasmas 14, 113503 (2007)]. The effort has also been made to detect the warm electrons, which are necessary for ionization, because Helicon discharges are of high density, low T{sub e} discharges and the tail of the bulk electron population may not have sufficient high-energy electrons. Experimental set up also comprises of the mirror magnetic field. Measurements using RF compensated Langmuir probes [A. Ganguli et al., Plasma Sources Sci. Technol. 17, 015003 (2008)], B-dot probe and computations based on the theory shows that the warm electrons at low pressure (0.2-0.3 mTorr) Helicon discharges, are because of the Landau damping of TG waves. In collisional environment, at a pressure Almost-Equal-To 10 mTorr, these high-energy electrons are due to the acceleration of bulk electrons from the neighboring regions across steep potential gradients possibly by the formation of double layers.
Colloquium: Physics of optical lattice clocks
Derevianko, Andrei; Katori, Hidetoshi
Recently invented and demonstrated optical lattice clocks hold great promise for improving the precision of modern time keeping. These clocks aim at the 10{sup -18} fractional accuracy, which translates into a clock that would neither lose nor gain a fraction of a second over an estimated age of the Universe. In these clocks, millions of atoms are trapped and interrogated simultaneously, dramatically improving clock stability. Here the principles of operation of these clocks are discussed and, in particular, a novel concept of magic trapping of atoms in optical lattices. Recently proposed microwave lattice clocks are also highlights and several applications that employ the optical lattice clocks as a platform for precision measurements and quantum information processing.
Colloquium: Serendipity and the Teachable Moment.
ERIC Educational Resources Information Center
Belson, Sarah Irvine
Discusses how collaborative technologies and computer-based communication have influenced preservice teacher education. Considers the professor's relationship with online students; preparing teachers to interact with students through the new technologies; and the professor as role model for good teaching and facilitator of learning. (LRW)
View graphs for GSFC Colloquium on OFMspert
NASA Technical Reports Server (NTRS)
Mitchell, Christine M.
Viewgraphs providing an overview of activities concerned with the development and testing of the Operator Function Model (OFM) expert system (OFMspert) are presented. The OFM is a mathematical tool for representing operator interaction with predominantly automated space ground control systems. OFM provides cognitive task analysis and served as the basis for the design of an intelligent operator's associate called OMFspert. An experimental implementation of OFMspert, referred to as Ally, was developed. An empirical evaluation of Ally was conducted to determine the effectiveness of a supervisory control team consisting of a human operator and Ally versus a control team consisting of two human operators. The experiment was carried out in the GT-MSOCC (Georgia Tech MultiSatellite Operations Control Center) domain, a research tool consisting of a high fidelity implementation of the operator interface to a GSFC ground control system. The viewgraphs outline the experimental design, operator performance measures, and preliminary results.
Colloquium paper: terrestrial apes and phylogenetic trees.
Arsuaga, Juan Luis
The image that best expresses Darwin's thinking is the tree of life. However, Darwin's human evolutionary tree lacked almost everything because only the Neanderthals were known at the time and they were considered one extreme expression of our own species. Darwin believed that the root of the human tree was very deep and in Africa. It was not until 1962 that the root was shown to be much more recent in time and definitively in Africa. On the other hand, some neo-Darwinians believed that our family tree was not a tree, because there were no branches, but, rather, a straight stem. The recent years have witnessed spectacular discoveries in Africa that take us close to the origin of the human tree and in Spain at Atapuerca that help us better understand the origin of the Neanderthals as well as our own species. The final form of the tree, and the number of branches, remains an object of passionate debate. PMID:20445090
Colloquium: Large scale simulations on GPU clusters
NASA Astrophysics Data System (ADS)
Bernaschi, Massimo; Bisson, Mauro; Fatica, Massimiliano
Graphics processing units (GPU) are currently used as a cost-effective platform for computer simulations and big-data processing. Large scale applications require that multiple GPUs work together but the efficiency obtained with cluster of GPUs is, at times, sub-optimal because the GPU features are not exploited at their best. We describe how it is possible to achieve an excellent efficiency for applications in statistical mechanics, particle dynamics and networks analysis by using suitable memory access patterns and mechanisms like CUDA streams, profiling tools, etc. Similar concepts and techniques may be applied also to other problems like the solution of Partial Differential Equations.
NASA Astrophysics Data System (ADS)
Nunes, I.; JET Contributors
Operation with a Be/W wall at JET (JET-ILW) has an impact on scenario development and energy confinement with respect to the carbon wall (JET-C). The main differences observed were (1) strong accumulation of W in the plasma core and (2) the need to mitigate the divertor target temperature to avoid W sputtering by Be and other low Z impurities and (3) a decrease of plasma energy confinement. A major difference is observed on the pedestal pressure, namely a reduction of the pedestal temperature which, due to profile stiffness the plasma core temperature is also reduced leading to a degradation of the global confinement. This effect is more pronounced in low β N scenarios. At high β N, the impact of the wall on the plasma energy confinement is mitigated by the weaker plasma energy degradation with power relative to the IPB98(y, 2) scaling calculated empirically for a CFC first wall. The smaller tolerable impurity concentration for tungsten (<10-5) compared to that of carbon requires the use of electron heating methods to prevent W accumulation in the plasma core region as well as gas puffing to avoid W entering the plasma core by ELM flushing and reduction of the W source by decreasing the target temperature. W source and the target temperature can also be controlled by impurity seeding. Nitrogen and Neon have been used and with both gases the reduction of the W source and the target temperature is observed. Whilst more experiments with Neon are necessary to assess its impact on energy confinement, a partial increase of plasma energy confinement is observed with Nitrogen, through the increase of edge temperature. The challenge for scenario development at JET is to extend the pulse length curtailed by its transient behavior (W accumulation or MHD), but more importantly by the divertor target temperature limits. Re-optimisation of the scenarios to mitigate the effect of the change of wall materials maintaining high global energy confinement similar to JET-C is
Optical plasma torch electron bunch generation in plasma wakefield accelerators
NASA Astrophysics Data System (ADS)
Wittig, G.; Karger, O.; Knetsch, A.; Xi, Y.; Deng, A.; Rosenzweig, J. B.; Bruhwiler, D. L.; Smith, J.; Manahan, G. G.; Sheng, Z.-M.; Jaroszynski, D. A.; Hidding, B.
A novel, flexible method of witness electron bunch generation in plasma wakefield accelerators is described. A quasistationary plasma region is ignited by a focused laser pulse prior to the arrival of the plasma wave. This localized, shapeable optical plasma torch causes a strong distortion of the plasma blowout during passage of the electron driver bunch, leading to collective alteration of plasma electron trajectories and to controlled injection. This optically steered injection is more flexible and faster when compared to hydrodynamically controlled gas density transition injection methods.
Plasma wakefield acceleration in self-ionized gas or plasmas.
Deng, S; Barnes, C D; Clayton, C E; O'Connell, C; Decker, F J; Erdem, O; Fonseca, R A; Huang, C; Hogan, M J; Iverson, R; Johnson, D K; Joshi, C; Katsouleas, T; Krejcik, P; Lu, W; Marsh, K A; Mori, W B; Muggli, P; Tsung, F
Tunnel ionizing neutral gas with the self-field of a charged particle beam is explored as a possible way of creating plasma sources for a plasma wakefield accelerator [Bruhwiler et al., Phys. Plasmas (to be published)]. The optimal gas density for maximizing the plasma wakefield without preionized plasma is studied using the PIC simulation code OSIRIS [R. Hemker et al., in Proceeding of the Fifth IEEE Particle Accelerator Conference (IEEE, 1999), pp. 3672-3674]. To obtain wakefields comparable to the optimal preionized case, the gas density needs to be seven times higher than the plasma density in a typical preionized case. A physical explanation is given. PMID:14683089
NASA Astrophysics Data System (ADS)
Reardon, Jim; Sprott, Clint
The ongoing Wonders of Physics outreach program at the University of Wisconsin has teamed up with the new Center for Magnetic Self-Organization of Laboratory and Astrophysical Plasmas (CMSO), an NSF Physics Frontier Center, in a variety of outreach efforts intended to attract students to plasma physics. Chief among these efforts are a live-action calculus competition--the ``Integration Bee''--in which students compete for prizes by doing integrals at the blackboard, and a video, tentatively entitled the ``Wonders of Plasma,'' which introduces CMSO-related plasma physics to a high-school level audience. Meanwhile, the Wonders of Physics continues to ``win fans for physics'' by putting on entertaining and informative shows before live audiences at the University of Wisconsin and elsewhere. Approximately 10,000 people have seen a Wonders of Physics show since the last APS DPP conference. Several new fusion-related demonstrations have been added to the Wonders of Physics Traveling Show in the past year. Some of them can be seen at the conference at the Plasma Expo on Thursday and Friday. This work supported by US DOE and NSF.
McIlwain, Michael E.; Grant, Jonathan F.; Golenko, Zsolt; Wittstein, Alan D.
An ignition device of the plasma jet type is disclosed. The device has a cylindrical cavity formed in insulating material with an electrode at one end. The other end of the cylindrical cavity is closed by a metal plate with a small orifice in the center which plate serves as a second electrode. An arc jumping between the first electrode and the orifice plate causes the formation of a highly-ionized plasma in the cavity which is ejected through the orifice into the engine cylinder area to ignite the main fuel mixture. Two improvements are disclosed to enhance the operation of the device and the length of the plasma plume. One improvement is a metal hydride ring which is inserted in the cavity next to the first electrode. During operation, the high temperature in the cavity and the highly excited nature of the plasma breaks down the metal hydride, liberating hydrogen which acts as an additional fuel to help plasma formation. A second improvement consists of a cavity insert containing a plurality of spaced, metal rings. The rings act as secondary spark gap electrodes reducing the voltage needed to maintain the initial arc in the cavity.
Plasma treatment of onychomycosis
NASA Astrophysics Data System (ADS)
Xiong, Zilan; Roe, Jeff; Grammer, Tim; Him, Yeon-Ho; Graves, David B.
Onychomycosis or fungal infection of the toenail or fingernail is a common affliction. Approximately 10% of the world's adult population is estimated to suffer from onychomycosis. Current treatment options such as topical creams, oral drugs, or laser treatments are generally limited by a variety of problems. We present results for an alternative onychomycosis treatment scheme using atmospheric pressure cold air plasmas. Using thinned cow hoof as a model nail material, we tested the ability of various plasma sources to act through the model nail to eradicate either bacteria or fungus deposited on the opposite side. Following 20 minute exposure to a surface microdischarge (SMD) device operating in room air, we observed a ~ 2 log reduction of E. coli. A similar result was obtained against T. rubrum after 45 min plasma treatment. NOx species concentration penetrating through the model nail as well as uptake into the nail were measured as a function of nail thickness. We propose that these plasma-generated species, or perhaps their reaction products, are responsible for at least part of the observed anti-microbial effect. We also explore the use of ultraviolet light acting in synergy with plasma-generated chemical species.
NASA Astrophysics Data System (ADS)
Messerle, V. E.; Ustimenko, A. B.
Results of many years of investigations of plasma-chemical technologies for pyrolysis, hydrogenation, thermochemical preparation for combustion, gasification, and complex reprocessing of solid fuels and hydrocarbon gas cracking are represented. Application of these technologies for obtaining the desired products (hydrogen, industrial carbon, synthesis gas, valuable components of the mineral mass of coal) corresponds to modern ecological and economical requirements to the power engineering, metallurgy, and chemical industry. Plasma fuel utilization technologies are characterized by the short-term residence of reagents within a reactor and the high degree of the conversion of source substances into the desired products without catalyst application. The thermochemical preparation of the fuel to combustion is realized in a plasma-fuel system presenting a reaction chamber with a plasmatron; and the remaining plasma fuel utilization technologies, in a combined plasma-chemical reactor with a nominal power of 100 kW, whose zone of the heat release from an electric arc is joined with the chemical reaction zone.
Low Temperature Plasma Medicine
NASA Astrophysics Data System (ADS)
Graves, David
Ionized gas plasmas near room temperature are used in a remarkable number of technological applications mainly because they are extraordinarily efficient at exploiting electrical power for useful chemical and material transformations near room temperature. In this tutorial address, I will focus on the newest area of low temperature ionized gas plasmas (LTP), in this case operating under atmospheric pressure conditions, in which the temperature-sensitive material is living tissue. LTP research directed towards biomedical applications such as sterilization, surgery, wound healing and anti-cancer therapy has seen remarkable growth in the last 3-5 years, but the mechanisms responsible for the biomedical effects have remained mysterious. It is known that LTP readily create reactive oxygen species (ROS) and reactive nitrogen species (RNS). ROS and RNS (or RONS), in addition to a suite of other radical and non-radical reactive species, are essential actors in an important sub-field of aerobic biology termed ``redox'' (or oxidation-reduction) biology. I will review the evidence suggesting that RONS generated by plasmas are responsible for their observed therapeutic effects. Other possible bio-active mechanisms include electric fields, charges and photons. It is common in LTP applications that synergies between different mechanisms can play a role and I will review the evidence for synergies in plasma biomedicine. Finally, I will address the challenges and opportunities for plasma physicists to enter this novel, multidisciplinary field.
Mechanisms of Plasma Therapeutics
NASA Astrophysics Data System (ADS)
Graves, David
In this talk, I address research directed towards biomedical applications of atmospheric pressure plasma such as sterilization, surgery, wound healing and anti-cancer therapy. The field has seen remarkable growth in the last 3-5 years, but the mechanisms responsible for the biomedical effects have remained mysterious. It is known that plasmas readily create reactive oxygen species (ROS) and reactive nitrogen species (RNS). ROS and RNS (or RONS), in addition to a suite of other radical and non-radical reactive species, are essential actors in an important sub-field of aerobic biology termed ``redox'' (or oxidation-reduction) biology. It is postulated that cold atmospheric plasma (CAP) can trigger a therapeutic shielding response in tissue in part by creating a time- and space-localized, burst-like form of oxy-nitrosative stress on near-surface exposed cells through the flux of plasma-generated RONS. RONS-exposed surface layers of cells communicate to the deeper levels of tissue via a form of the ``bystander effect,'' similar to responses to other forms of cell stress. In this proposed model of CAP therapeutics, the plasma stimulates a cellular survival mechanism through which aerobic organisms shield themselves from infection and other challenges.
Pulsed Plasma Accelerator Modeling
NASA Technical Reports Server (NTRS)
Goodman, M.; Kazeminezhad, F.; Owens, T.
This report presents the main results of the modeling task of the PPA project. The objective of this task is to make major progress towards developing a new computational tool with new capabilities for simulating cylindrically symmetric 2.5 dimensional (2.5 D) PPA's. This tool may be used for designing, optimizing, and understanding the operation of PPA s and other pulsed power devices. The foundation for this task is the 2-D, cylindrically symmetric, magnetohydrodynamic (MHD) code PCAPPS (Princeton Code for Advanced Plasma Propulsion Simulation). PCAPPS was originally developed by Sankaran (2001, 2005) to model Lithium Lorentz Force Accelerators (LLFA's), which are electrode based devices, and are typically operated in continuous magnetic field to the model, and implementing a first principles, self-consistent algorithm to couple the plasma and power circuit that drives the plasma dynamics.
NASA Technical Reports Server (NTRS)
Foster, John (Inventor); Patterson, Michael (Inventor)
An all permanent magnet Electron Cyclotron Resonance, large diameter (e.g., 40 cm) plasma source suitable for ion/plasma processing or electric propulsion, is capable of producing uniform ion current densities at its exit plane at very low power (e.g., below 200 W), and is electrodeless to avoid sputtering or contamination issues. Microwave input power is efficiently coupled with an ionizing gas without using a dielectric microwave window and without developing a throat plasma by providing a ferromagnetic cylindrical chamber wall with a conical end narrowing to an axial entrance hole for microwaves supplied on-axis from an open-ended waveguide. Permanent magnet rings are attached inside the wall with alternating polarities against the wall. An entrance magnet ring surrounding the entrance hole has a ferromagnetic pole piece that extends into the chamber from the entrance hole to a continuing second face that extends radially across an inner pole of the entrance magnet ring.
Cooking strongly coupled plasmas
NASA Astrophysics Data System (ADS)
Clérouin, Jean
We present the orbital-free method for dense plasmas which allows for efficient variable ionisation molecular dynamics. This approach is a literal application of density functional theory where the use of orbitals is bypassed by a semi-classical estimation of the electron kinetic energy through the Thomas-Fermi theory. Thanks to a coherent definition of ionisation, we evidence a particular regime in which the static structure no longer depends on the temperature: the Γ-plateau. With the help of the well-known Thomas-Fermi scaling laws, we derive the conditions required to obtain a plasma at a given value of the coupling parameter and deduce useful fits. Static and dynamical properties are predicted as well as a a simple equation of state valid on the Γ-plateau. We show that the one component plasma model can be helpful to describe the correlations in real systems.
Fundamentals of plasma simulation
Forslund, D.W.
With the increasing size and speed of modern computers, the incredibly complex nonlinear properties of plasmas in the laboratory and in space are being successfully explored in increasing depth. Of particular importance have been numerical simulation techniques involving finite size particles on a discrete mesh. After discussing the importance of this means of understanding a variety of nonlinear plasma phenomena, we describe the basic elements of particle-in-cell simulation and their limitations and advantages. The differencing techniques, stability and accuracy issues, data management and optimization issues are discussed by means of a simple example of a particle-in-cell code. Recent advances in simulation methods allowing large space and time scales to be treated with minimal sacrifice in physics are reviewed. Various examples of nonlinear processes successfully studied by plasma simulation will be given.
Plasma contactor research, 1990
NASA Technical Reports Server (NTRS)
Williams, John D.; Wilbur, Paul J.
Emissive and Langmuir probes were used to measure plasma potential profiles, plasma densities, electron energy distributions, and plasma noise levels near a hollow cathode-based plasma contactor emitting electrons. The effects of electron emission current (100 to 1500 mA) and contactor flowrate (2 to 10 sccm (Xenon)) on these data are examined. Retarding potential analyzer (RPA) measurements showing that high energy ions generally stream from a contactor along with the electrons being emitted are also presented, and a mechanism by which this occurs is postulated. This mechanism, which involves a high rate of ionization induced between electrons and atoms flowing together from the hollow cathode orifice, results in a region of high positive space charge and high positive potential. Langmuir and RPA probe data suggests that both electrons and ions expand spherically from this potential hill region. In addition to experimental observations, a simple one-dimensional model which describes the electron emission process and predicts the phenomena just mentioned is presented and is shown to agree qualitatively with these observations. Experimental results of the first stage of bilateral cooperation with the Italian Institute of Interplanetary Space Physics (IFSI CNR) are presented. Sharp, well-defined double layers were observed downstream of a contactor collecting electrons from an ambient plasma created in the IFSI Facility. The voltage drop across these double layers was observed to increase with the current drawn from the ambient plasma. This observation, which was not as clear in previous IFSI tests conducted at higher neutral pressures, is in agreement with previous experimental observations made at both Colorado State University and NASA Lewis Research Center. Greater double layer voltage drops, multiple double layers, and higher noise levels in the region near the double layers were also observed when a magnetic field was imposed and oriented perpendicular to the
Greenwald, Martin
Many others in the fusion energy and advanced scientific computing communities participated in the development of this plan. The core planning team is grateful for their important contributions. This summary is meant as a quick overview the Fusion Simulation Program's (FSP's) purpose and intentions. There are several additional documents referenced within this one and all are supplemental or flow down from this Program Plan. The overall science goal of the DOE Office of Fusion Energy Sciences (FES) Fusion Simulation Program (FSP) is to develop predictive simulation capability for magnetically confined fusion plasmas at an unprecedented level of integration and fidelity. This will directly support and enable effective U.S. participation in International Thermonuclear Experimental Reactor (ITER) research and the overall mission of delivering practical fusion energy. The FSP will address a rich set of scientific issues together with experimental programs, producing validated integrated physics results. This is very well aligned with the mission of the ITER Organization to coordinate with its members the integrated modeling and control of fusion plasmas, including benchmarking and validation activities. [1]. Initial FSP research will focus on two critical Integrated Science Application (ISA) areas: ISA1, the plasma edge; and ISA2, whole device modeling (WDM) including disruption avoidance. The first of these problems involves the narrow plasma boundary layer and its complex interactions with the plasma core and the surrounding material wall. The second requires development of a computationally tractable, but comprehensive model that describes all equilibrium and dynamic processes at a sufficient level of detail to provide useful prediction of the temporal evolution of fusion plasma experiments. The initial driver for the whole device model will be prediction and avoidance of discharge-terminating disruptions, especially at high performance, which are a critical
Partial pressure analysis of plasmas
Dylla, H.F.
The application of partial pressure analysis for plasma diagnostic measurements is reviewed. A comparison is made between the techniques of plasma flux analysis and partial pressure analysis for mass spectrometry of plasmas. Emphasis is given to the application of quadrupole mass spectrometers (QMS). The interface problems associated with the coupling of a QMS to a plasma device are discussed including: differential-pumping requirements, electromagnetic interferences from the plasma environment, the detection of surface-active species, ion source interactions, and calibration procedures. Example measurements are presented from process monitoring of glow discharge plasmas which are useful for cleaning and conditioning vacuum vessels.
Features of terrestrial plasma transport
NASA Technical Reports Server (NTRS)
Moore, T. E.; Chandler, M. O.; Chappell, C. R.; Pollock, C. J.; Waite, J. H., Jr.
Research concerning the transport and distribution of ionospheric plasma in the magnetosphere are reviewed, stressing the dichotomy in explanations given for the low plasma densities outside the plasmasphere. The convection/hot solar plasma model and the convection/loss model are considered. Observations of global ionospheric outflows are compared with theoretical studies. It is suggested that there is a need for a hybrid model of magnetospheric plasma in which terrestrial plasma is both lost into the solar wind and energized and trapped within the magnetosphere, inflating the geomagnetic field and excluding cold plasma from conjugate regions.
Railgun plasma armature characterisation experiments
NASA Astrophysics Data System (ADS)
Richardson, D. D.
A plasma armature characterization experiment (PACE) is described. The PACE device is designed to study the plasma armature of railguns and yields information on properties such as temperature, pressure, densities, plasma potential, and ion species with their degrees of ionization. The main experimental studies are by spectroscopy of the light emitted and by Langmuir probes. The device simulates the plasma moving behind the projectile in a railgun by a static plasma held by electromagnetic forces against a fixed wall. Results to date demonstrate the feasibility of the concept and indicate improvements to the device which ensure that much useful information on railgun plasmas is forthcoming.
BOUT is a parallelized 3D nonlocal electromagnetic turbulence code. The principal calculations are the boundary plasma turbulence in a realistic magnetic geometry. BOUT uses fluid Braginskii equations for plasma vorticity, density, electron and ion temperature and Parallel mementum. With sources added in the core-edge region and sinks in the scrape-off-layer (SOL), BOUT follows the self-consistent profile evolution together with turbulence. BOUT also includes coupling to a magnetohyfrodynamic equlibrium (EFIT package) and a two-dimensional hydrodynamic edgemore » transport model (UEDGE package).« less
NASA Technical Reports Server (NTRS)
Rust, D. M.
The present paper deals with explosions in a magnetized solar plasma, known as flares, whose effects are seen throughout the electromagnetic spectrum, from gamma-rays through the visible and to the radio band. The diverse phenomena associated with flares are discussed, along with the physical mechanisms that have been advanced to explain them. The impact of solar flare research on the development of plasma physics and magnetohydrodynamics is noted. The rapid development of solar flare research during the past 20 years, owing to the availability of high-resolution images, detailed magnetic field measurements, and improved spectral data, is illustrated.
Phillips, J.A.; Suydam, R.; Tuck, J.L.
BS>A plasma confining and heating reactor is described which has the form of a torus with a B/sub 2/ producing winding on the outside of the torus and a helical winding of insulated overlapping tunns on the inside of the torus. The inner helical winding performs the double function of shielding the plasma from the vitreous container and generating a second B/sub z/ field in the opposite direction to the first B/sub z/ field after the pinch is established.
NASA Technical Reports Server (NTRS)
Computer aided, fully-automatic TRW system sprays very hot plasma onto a turbine blade. Composed of gas into which metallic and ceramic powders have been injected, the plasma forms a two-layer coating which insulates the blade. Critical part of operation is controlling the thickness of the deposit which is measured in thousandths of an inch. This is accomplished by an optical detector which illuminates spots at various locations on the blade and determines thickness by measuring the light reflections. Optical sensor monitors spraying process until precise thickness is attained, then computer halts the spraying.
NASA Technical Reports Server (NTRS)
Harries, W. L.
The possibility of creating a plasma from fission fragments was investigated, as well as the probability of utilizing the energy of these particles to create population inversion leading to laser action. Eventually, it is hoped that the same medium could be used for both fissioning and lasing, thus avoiding inefficiences in converting one form of energy to the other. A central problem in understanding a fission induced plasma is to obtain an accurate model of the electron behavior; some calculations are presented to this end. The calculations are simple, providing a compendium of processes for reference.
NASA Astrophysics Data System (ADS)
Freytsis, Marat; Gralla, Samuel E.
Magnetars are surrounded by diffuse plasma in magnetic field strengths well above the quantum electrodynamic critical value. We derive equations of ``quantum force-free electrodynamics'' for this plasma using effective field theory arguments. We argue that quantum effects do not modify the large scale structure of the magnetosphere, and in particular that the spin-down rate does not deviate significantly from the classical result. We provide definite evolution equations that can be used to explore potentially important small-scale corrections, such as shock formation, which has been proposed as a mechanism for both burst and quiescent emission from magnetars.
Condensed Plasmas under Microgravity
NASA Technical Reports Server (NTRS)
Morfill, G. E.; Thomas, H. M.; Konopka, U.; Rothermel, H.; Zuzic, M.; Ivlev, A.; Goree, J.; Rogers, Rick (Technical Monitor)
Experiments under microgravity conditions were carried out to study 'condensed' (liquid and crystalline) states of a colloidal plasma (ions, electrons, and charged microspheres). Systems with approximately 10(exp 6) microspheres were produced. The observed systems represent new forms of matter--quasineutral, self-organized plasmas--the properties of which are largely unexplored. In contrast to laboratory measurements, the systems under microgravity are clearly three dimensional (as expected); they exhibit stable vortex flows, sometimes adjacent to crystalline regions, and a central 'void,' free of microspheres.
Plasma flow in peripheral region of detached plasma in linear plasma device
NASA Astrophysics Data System (ADS)
Hayashi, Y.; Ohno, N.; Kajita, S.; Tanaka, H.
A plasma flow structure is investigated using a Mach probe under detached plasma condition in a linear plasma device NAGDIS-II. A reverse flow along the magnetic field is observed in a steady-state at far-peripheral region of the plasma column in the upstream side from the recombination front. These experimental results indicate that plasma near the recombination front should strongly diffuse across the magnetic field, and it should be transported along the magnetic field in the reverse flow direction. Furthermore, bursty plasma density fluctuations associated with intermittent convective plasma transport are observed in the far-peripheral region of the plasma column in both upstream and downstream sides from the recombination front. Such a nondiffusive transport can contribute to the intermittent reverse plasma flow, and the experimental results indicate that intermittent transports are frequently produced near the recombination front.
Plasma heating power dissipation in low temperature hydrogen plasmas
Komppula, J. Tarvainen, O.
A theoretical framework for power dissipation in low temperature plasmas in corona equilibrium is developed. The framework is based on fundamental conservation laws and reaction cross sections and is only weakly sensitive to plasma parameters, e.g., electron temperature and density. The theory is applied to low temperature atomic and molecular hydrogen laboratory plasmas for which the plasma heating power dissipation to photon emission, ionization, and chemical potential is calculated. The calculated photon emission is compared to recent experimental results.
Laser-plasma-based linear collider using hollow plasma channels
NASA Astrophysics Data System (ADS)
Schroeder, C. B.; Benedetti, C.; Esarey, E.; Leemans, W. P.
A linear electron-positron collider based on laser-plasma accelerators using hollow plasma channels is considered. Laser propagation and energy depletion in the hollow channel is discussed, as well as the overall efficiency of the laser-plasma accelerator. Example parameters are presented for a 1-TeV and 3-TeV center-of-mass collider based on laser-plasma accelerators.
Thermal plasma processing of materials
Pfender, E.; Heberlein, J.
Emphasis has been on plasma synthesis of fine powders, plasma Chemical Vapor Deposition (CVD), on related diagnostics, and on modeling work. Since plasma synthesis as well as plasma CVD make frequent use of plasma jets, the beginning has been devoted of plasma jets and behavior of particulates injected into such plasma jets. Although most of the construction of the Triple-Torch Plasma Reactor (TTPR) has already been done, modifications have been made in particular modifications required for plasma CVD of diamond. A new reactor designed for Counter-Flow Liquid Injection Plasma Synthesis (CFLIPS) proved to be an excellent tool for synthesis of fine powders as well as for plasma CVD. An attempt was made to model flow and temperature fields in this reactor. Substantial efforts were made to single out those parameters which govern particle size, size distribution, and powder quality in our plasma synthesis experiments. This knowledge is crucial for controlling the process and for meaningful diagnostics and modeling work. Plasma CVD of diamond films using both reactors has been very successful and we have been approached by a number of companies interested in using this technology for coating of tools.
Modelling the Plasma Jet in Multi-Arc Plasma Spraying
NASA Astrophysics Data System (ADS)
Bobzin, K.; Öte, M.; Schein, J.; Zimmermann, S.; Möhwald, K.; Lummer, C.
Particle in-flight characteristics in atmospheric plasma spraying process are determined by impulse and heat energy transferred between the plasma jet and injected powder particles. One of the important factors for the quality of the plasma-sprayed coatings is thus the distribution of plasma gas temperatures and velocities in plasma jet. Plasma jets generated by conventional single-arc plasma spraying systems and their interaction with powder particles were subject matter of intensive research. However, this does not apply to plasma jets generated by means of multi-arc plasma spraying systems yet. In this study, a numerical model has been developed which is designated to dealing with the flow characteristics of the plasma jet generated by means of a three-cathode spraying system. The upstream flow conditions, which were calculated using a priori conducted plasma generator simulations, have been coupled to the plasma jet simulations. The significances of the relevant numerical assumptions and aspects of the models are analyzed. The focus is placed on to the turbulence and diffusion/demixing modelling. A critical evaluation of the prediction power of the models is conducted by comparing the numerical results to the experimental results determined by means of emission spectroscopic computed tomography. It is evident that the numerical models exhibit a good accuracy for their intended use.
Computations in Plasma Physics.
ERIC Educational Resources Information Center
Cohen, Bruce I.; Killeen, John
Discusses contributions of computers to research in magnetic and inertial-confinement fusion, charged-particle-beam propogation, and space sciences. Considers use in design/control of laboratory and spacecraft experiments and in data acquisition; and reviews major plasma computational methods and some of the important physics problems they…
Langdon, A.B.
Implicit time integration methods have been used extensively in numerical modelling of slowly varying phenomena in systems that also support rapid variation. Examples include diffusion, hydrodynamics and reaction kinetics. This article discussed implementation of implicit time integration in plasma codes of the ''particle-in-cell'' family, and the benefits to be gained.
Joshi, Chandershekhar; Shukla, Pradeep
The aim of the article is to present a report on the clinical presentation of plasma cell gingivitis with the use of herbal toothpowder. Plasma cell gingivitis [PCG] is a rare benign condition of the gingiva characterized by sharply demarcated erythematous and edematous gingivitis often extending to the mucogingival junction. As the name suggests it is diffuse and massive infiltration of plasma cells into the sub-epithelial gingival tissue. It is a hypersensitivity reaction to some antigen, often flavouring agents or spices found in chewing gums, toothpastes and lorenzes. A 27-yr old male with a chief complaint of painful, bleeding swollen mass in his lower front teeth region with prolong use of herbal toothpowder. The gingiva bled readily on probing. Patient was advised to refrain from the use of herbal toothpowder and along with periodontal treatment, no further reoccurrence was found. as more and more herbal products are gaining popularity, clinicians should be aware of effects of these products. Early diagnosis is essential as plasma cell gingivitis has similar pathologic changes seen clinically as in leukemia, HIV infection, discoid lupus erythematosis, atrophic lichen planus, desquamative gingivitis, or cicatrical pemphigoid which must be differentiated through hematologic and serologic testing. PMID:26015677
NASA Technical Reports Server (NTRS)
Holmes, Richard R.; Mckechnie, Timothy N.
Currently, protective plasma spray coatings are applied to space shuttle main engine turbine blades of high-performance nickel alloys by an air plasma spray process. Originally, a ceramic coating of yttria-stabilized zirconia (ZrO2.12Y2O3) was applied for thermal protection, but was removed because of severe spalling. In vacuum plasma spray coating, plasma coatings of nickel-chromium-aluminum-yttrium (NiCrAlY) are applied in a reduced atmosphere of argon/helium. These enhanced coatings showed no spalling after 40 MSFC burner rig thermal shock cycles between 927 C (1700 F) and -253 C (-423 F), while current coatings spalled during 5 to 25 test cycles. Subsequently, a process was developed for applying a durable thermal barrier coating of ZrO2.8Y2O3 to the turbine blades of first-stage high-pressure fuel turbopumps utilizing the enhanced NiCrAlY bond-coating process. NiCrAlY bond coating is applied first, with ZrO2.8Y2O3 added sequentially in increasing amounts until a thermal barrier coating is obtained. The enchanced thermal barrier coating has successfully passed 40 burner rig thermal shock cycles.
Magnetospheric space plasma investigations
NASA Technical Reports Server (NTRS)
Comfort, Richard H.; Horwitz, James L.
The topics addressed are: (1) generalized semikinetic models; (2) collision-collisionless transition model; (3) observation of O+ outflows; (4) equatorial transitions; (5) inner plasmasphere-ionosphere coupling; (6) plasma wave physical processes; (7) ULF wave ray-tracing; and (8) nighttime anomalous electron heating events.
Laboratory plasma probe studies
NASA Technical Reports Server (NTRS)
Heikkila, W. J.
Diagnostic experiments performed in a collisionless plasma using CO2 as the working gas are described. In particular, simultaneous measurements that have been performed by means of Langmuir- and RF-probes are presented. A resonance occurring above the parallel resonance in the frequency characteristic of a two electrode system is interpreted as being due to the resonant excitation of electroacoustic waves.
ERIC Educational Resources Information Center
Stifle, Jack
A graphics terminal designed for use as a remote computer input/output terminal is described. Although the terminal is intended for use in teaching applications, it has several features which make it useful in many other computer terminal applications. These features include: a 10-inch square plasma display panel, permanent storage of information…
Microscopic plasma Hamiltonian
NASA Technical Reports Server (NTRS)
Peng, Y.-K. M.
A Hamiltonian for the microscopic plasma model is derived from the Low Lagrangian after the dual roles of the generalized variables are taken into account. The resulting Hamilton equations are shown to agree with the Euler-Lagrange equations of the Low Lagrangian.
Filamentary magnetohydrodynamic plasmas
Kinney, R.; Tajima, T.; Petviashvili, N.; McWilliams, J.C.
A filamentary construct of magnetohydrodynamical plasma dynamics, based on the Elsasser variables was developed. This approach is modeled after discrete vortex models of hydrodynamical turbulence, which cannot be expected in general to produce results identical to ones based on a Fourier decomposition of the fields. In a highly intermittent plasma, the induction force is small compared to the convective motion, and when this force is neglected. the plasma vortex system is described by a Hamiltonian. For a system with many such vortices we present a statistical treatment of a collection of discrete current-vorticity concentrations. Canonical and microcanonical statistical calculations show that both the vorticity and the current spectra are peaked at long wavelengths, and the expected states revert to known hydrodynamical states as the magnetic field vanishes. These results differ from previous Fourier-based statistical theories. but it is found that when the filament calculation is expanded to include the inductive force, the results approach the Fourier equilibria in the low-temperature limit, and the previous Hamiltonian plasma vortex results in the high-temperature limit. Numerical simulations of a large number of filaments are carried out and support the theory. A three-dimensional vortex model is outlined as well, which is also Hamiltonian when the inductive force is neglected.
NASA Technical Reports Server (NTRS)
Dennis, Brian R.; Dan, Chau; Jain, Rajmal; Schwartz, Richard A.; Tolbert, Anne K.
The equivalent width of the iron-line complex at 6.7 keV seen in flare X-ray spectra suggests that the iron abundance of the hottest plasma at temperatures >approx.10 MK may sometimes be significantly lower than the nominal coronal abundance of four times the photospheric value that is commonly assumed. This conclusion is based on X-ray spectral observations of several flares seen in common with the Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and the Solar X-ray Spectrometer (SOXS) on the second Indian geostationary satellite, GSAT-2. The implications of this will be discussed as it relates to the origin of the hot flare plasma - either plasma already in the corona that is directly heated during the flare energy release process or chromospheric plasma that is heated by flare-accelerated particles and driven up into the corona. Other possible explanations of lower-than-expected equivalent widths of the iron-line complex will also be discussed.
NASA Astrophysics Data System (ADS)
Malka, Victor
The continuing development of powerful laser systems has permitted to extend the interaction of laser beams with matter far into the relativistic domain, and to demonstrate new approaches for producing energetic particle beams. The extremely large electric fields, with amplitudes exceeding the TV/m level, that are produced in plasma medium are of relevance particle acceleration. Since the value of this longitudinal electric field, 10,000 times larger than those produced in conventional radio-frequency cavities, plasma accelerators appear to be very promising for the development of compact accelerators. The incredible progresses in the understanding of laser plasma interaction physic, allows an excellent control of electron injection and acceleration. Thanks to these recent achievements, laser plasma accelerators deliver today high quality beams of energetic radiation and particles. These beams have a number of interesting properties such as shortness, brightness and spatial quality, and could lend themselves to applications in many fields, including medicine, radio-biology, chemistry, physics and material science,security (material inspection), and of course in accelerator science.
Electrostatic Plasma Accelerator (EPA)
NASA Technical Reports Server (NTRS)
Brophy, John R.; Aston, Graeme
The Electrostatic Plasma Accelerator (EPA) is a thruster concept which promises specific impulse levels between low power arcjets and those of the ion engine while retaining the relative simplicity of the arcjet. The EPA thruster produces thrust through the electrostatic acceleration of a moderately dense plasma. No accelerating electrodes are used and the specific impulse is a direct function of the applied discharge voltage and the propellant atomic mass. The goal of the present program is to demonstrate feasibility of the EPA thruster concept through experimental and theoretical investigations of the EPA acceleration mechanism and discharge chamber performance. Experimental investigations will include operating the test bed ion (TBI) engine as an EPA thruster and parametrically varying the thruster geometry and operating conditions to quantify the electrostatic plasma acceleration effect. The theoretical investigations will include the development of a discharge chamber model which describes the relationships between the engine size, plasma properties, and overall performance. For the EPA thruster to be a viable propulsion concept, overall thruster efficiencies approaching 30% with specific impulses approaching 1000 s must be achieved.
Filamentary magnetohydrodynamic plasmas
Kinney, R.; Tajima, T. ); McWilliams, J.C. ); Petviashvili, N. )
A filamentary construct of magnetohydrodynamical plasma dynamics based on the Elsaesser variables is developed. This approach is modeled after discrete vortex models of hydrodynamical turbulence, which cannot be expected in general to produce results identical to those based on a Fourier decomposition of the fields. In a highly intermittent plasma, the induction force is small compared to the convective motion, and when this force is neglected, the plasma vortex system is described by a Hamiltonian. A statistical treatment of a collection of discrete current-vorticity concentrations is given. Canonical and microcanonical statistical calculations show that both the vorticity and the current spectra are peaked at long wavelengths, and the expected states revert to known hydrodynamical states as the magnetic field vanishes. These results differ from previous Fourier-based statistical theories, but it is found that when the filament calculation is expanded to include the inductive force, the results approach the Fourier equilibria in the low-temperature limit, and the previous Hamiltonian plasma vortex results in the high-temperature limit. Numerical simulations of a large number of filaments are carried out and support the theory. A three-dimensional vortex model is presented as well, which is also Hamiltonian when the inductive force is neglected. A statistical calculation in the canonical ensemble and numerical simulations show that a nonzero large-scale magnetic field is statistically favored, and that the preferred shape of this field is a long, thin tube of flux. Possible applications to a variety of physical phenomena are suggested.
Filamentary magnetohydrodynamic plasmas
NASA Astrophysics Data System (ADS)
Kinney, R.; Tajima, T.; Petviashvili, N.; McWilliams, J. C.
A filamentary construct of magnetohydrodynamical plasma dynamics, based on the Elsasser variables was developed. This approach is modeled after discrete vortex models of hydrodynamical turbulence, which cannot be expected in general to produce results identical to ones based on a Fourier decomposition of the fields. In a highly intermittent plasma, the induction force is small compared to the convective motion, and when this force is neglected, the plasma vortex system is described by a Hamiltonian. For a system with many such vortices we present a statistical treatment of a collection of discrete current-vorticity concentrations. Canonical and microcanonical statistical calculations show that both the vorticity and the current spectra are peaked at long wavelengths, and the expected states revert to known hydrodynamical states as the magnetic field vanishes. These results differ from previous Fourier-based statistical theories, but it is found that when the filament calculation is expanded to include the inductive force, the results approach the Fourier equilibria in the low-temperature limit, and the previous Hamiltonian plasma vortex results in the high-temperature limit. Numerical simulations of a large number of filaments are carried out and support the theory. A three-dimensional vortex model is outlined as well, which is also Hamiltonian when the inductive force is neglected.
Process Sprays Uniforms Plasma Coatings
NASA Technical Reports Server (NTRS)
Sliney, H. E.; Jacobson, T. P.; Walther, G. C.; Nakamura, H. H.
Composite-powder processing procedure developed along with plasma-spray parameters to achieve homogeneous, well-bonded, low-porosity, self-lubricating coatings. Multicomponent plasma coatings are applied without segretation of components.
Recent results for plasma antennas
Alexeff, Igor; Anderson, Ted; Farshi, Esmaeil; Karnam, Naresh; Pulasani, Nanditha Reddy
Plasma antennas are just as effective as metal antennas. They can transmit, receive, and reflect radio waves just as well as metal antennas. In addition, plasma generated noise does not appear to be a problem.
Theory of the unmagnetized plasma.
NASA Technical Reports Server (NTRS)
Montgomery, D. C.
The Vlasov mathematical model of a plasma, which has come to be thought more useful than any other in describing the dynamical behavior of the majority of plasmas of interest, is first examined. Macroscopic variables and moment equations; linear electrostatics solutions; plasma oscillations, ion acoustic waves, and linear instabilities are treated, as well as external fields, 'test' charges, and nonlinear Vlasov phenomena. Plasmas are statistically described, and attention is given to the kinetic theory of the stable, uniform plasma and the Balescu-Lenard equation; two-time ensemble averages and fluctuation spectra in stable plasmas; the kinetic theory of the unstable plasma; and ensembles of Vlasov plasmas. Some illustrative experiments are described. Four appendixes deal with the electrostatic approximation and transverse waves; solution of the linearized Vlasov equation in a magnetic field; estimates of correlation functions from thermal equilibrium; and equivalence of spatially uniform BBGKY and Klimontovich correlations.
A microwave plasma cleaning apparatus
NASA Technical Reports Server (NTRS)
Tsai, C. C.; Nelson, W. D.; Schechter, D. E.; Thompson, L. M.; Glover, A. L.
In a microwave electron cyclotron resonance plasma source, reactive plasmas of oxygen and its mixtures of argon have been used for evaluating plasma cleaning technologies. Small aluminum samples (0.95 x 1.9 cm) were coated with thin films (less than or equal to 20 micrometers in thickness) of Shell Vitrea oil and cleaned with reactive plasmas. The discharge parameters, such as gas pressure, magnetic field, substrate biasing, and microwave power, were varied to change cleaning conditions. A mass spectroscopy (or residual gas analyzer) was used to monitor the status of plasma cleaning. Mass loss of the samples after plasma cleaning was measured to estimate cleaning rates. Measured cleaning rates of low-pressure (0.5-m torr) argon/oxygen plasmas were as high as 2.7 micrometers/min. X-ray photoelectron spectroscopy was used to determine cleanliness of the sample surfaces. In this paper, significant results of the plasma cleaning are reported and discussed.
Millimeter Wave Communication through Plasma
NASA Technical Reports Server (NTRS)
Bastin, Gary L.
Millimeter wave communication through plasma at frequencies of 35 GHz or higher shows promise in maintaining communications connectivity during rocket launch and re-entry, critical events which are typically plagued with communication dropouts. Extensive prior research into plasmas has characterized the plasma frequency at these events, and research at the Kennedy Space Center is investigating the feasibility of millimeter communication through these plasma frequencies.
Magnetoacoustic solitons in quantum plasma
Hussain, S.; Mahmood, S.
Nonlinear magnetoacoustic waves in collisionless homogenous, magnetized quantum plasma is studied. Two fluid quantum magneto-hydrodynamic model (QMHD) is employed and reductive perturbation method is used to derive Korteweg de Vries (KdV) equation for magnetoacoustic waves. The effects of plasma density and magnetic field intensity are investigated on magnetoacoustic solitary structures in quantum plasma. The numerical results are also presented, which are applicable to explain some aspects of the propagation of nonlinear magnetoacosutic wave in dense astrophysical plasma situations.
Studies on counterstreaming plasma expansion
NASA Technical Reports Server (NTRS)
Singh, N.; Thiemann, H.; Schunk, R. W.
Recent studies on counterstreaming plasma expansions are summarized. The basic phenomenon of plasma expansion is reviewed, and results from one-dimensional simulations of counterstreaming plasma expansion are discussed. Results from simulations based on an electrostatic particle-in-cell code, in which the dynamics of both the electrons and ions are exactly followed, are discussed. The formation of electrostatic shocks is addressed. Finally, results are presented on the ionospheric plasma expansion along the geomagnetic flux tubes by solving the hydrodynamic equations.
Plasma sources for spacecraft neutralization
NASA Technical Reports Server (NTRS)
Davis, V. A.; Katz, I.; Mandell, M. J.
The principles of the operation of plasma sources for the neutralization of the surface of a spacecraft traveling in the presence of hot plasma are discussed with special attention given to the hollow-cathode-based plasma contactors. Techiques are developed that allow the calculation of the potentials and particle densities in the near environment of a hollow cathode plasma contactor in both the test tank and the LEO environment. The techniques and codes were validated by comparison of calculated and measured results.
Experiments on Cryogenic Complex Plasma
Ishihara, O.; Sekine, W.; Kubota, J.; Uotani, N.; Chikasue, M.; Shindo, M.
Experiments on a cryogenic complex plasma have been performed. Preliminary experiments include production of a plasma in a liquid helium or in a cryogenic helium gas by a pulsed discharge. The extended production of a plasma has been realized in a vapor of liquid helium or in a cryogenic helium gas by rf discharge. The charge of dust particles injected in such a plasma has been studied in detail.
NASA Astrophysics Data System (ADS)
Akdim, Mohamed Reda
Nowadays plasmas are used for various applications such as the fabrication of silicon solar cells, integrated circuits, coatings and dental cleaning. In the case of a processing plasma, e.g. for the fabrication of amorphous silicon solar cells, a mixture of silane and hydrogen gas is injected in a reactor. These gases are decomposed by making a plasma. A plasma with a low degree of ionization (typically 10_5) is usually made in a reactor containing two electrodes driven by a radio-frequency (RF) power source in the megahertz range. Under the right circumstances the radicals, neutrals and ions can react further to produce nanometer sized dust particles. The particles can stick to the surface and thereby contribute to a higher deposition rate. Another possibility is that the nanometer sized particles coagulate and form larger micron sized particles. These particles obtain a high negative charge, due to their large radius and are usually trapped in a radiofrequency plasma. The electric field present in the discharge sheaths causes the entrapment. Such plasmas are called dusty or complex plasmas. In this thesis numerical models are presented which describe dusty plasmas in reactive and nonreactive plasmas. We started first with the development of a simple one-dimensional silane fluid model where a dusty radio-frequency silane/hydrogen discharge is simulated. In the model, discharge quantities like the fluxes, densities and electric field are calculated self-consistently. A radius and an initial density profile for the spherical dust particles are given and the charge and the density of the dust are calculated with an iterative method. During the transport of the dust, its charge is kept constant in time. The dust influences the electric field distribution through its charge and the density of the plasma through recombination of positive ions and electrons at its surface. In the model this process gives an extra production of silane radicals, since the growth of dust is
Magnetic Lens For Plasma Engine
NASA Technical Reports Server (NTRS)
Sercel, Joel C.
Low-field electromagnet coils placed downstream of plasma engine, polarized oppositely to higher-field but smaller radius coil in nozzle of engine, reduces divergence of plasma jet, thereby increasing efficiency of engine. Concept tested by computer simulation based on simplified mathematical model of plasma, engine, and coils.
Controlled zone microwave plasma system
Ripley, Edward B; Seals, Roland D; Morrell, Jonathan S
An apparatus and method for initiating a process gas plasma. A conductive plate having a plurality of conductive fingers is positioned in a microwave applicator. An arc forms between the conductive fingers to initiate the formation of a plasma. A transport mechanism may convey process materials through the plasma. A spray port may be provided to expel processed materials.
NASA Technical Reports Server (NTRS)
Rozanov, V. B.; Rukhadze, A. A.
The physical principles underlying the use of radiating plasmas for the optical pumping of lasers are described. Particular consideration is given to the properties of radiating plasmas; radiation selectivity; the dynamics, equilibrium, and stability of radiating plasmas; the radiative Reynolds number; and experimental results on radiating discharges.
Tomographic diagnostics of nonthermal plasmas
NASA Astrophysics Data System (ADS)
Denisova, Natalia
In the previous work [1], we discussed a ``technology'' of tomographic method and relations between the tomographic diagnostics in thermal (equilibrium) and nonthermal (nonequilibrium) plasma sources. The conclusion has been made that tomographic reconstruction in thermal plasma sources is the standard procedure at present, which can provide much useful information on the plasma structure and its evolution in time, while the tomographic reconstruction of nonthermal plasma has a great potential at making a contribution to understanding the fundamental problem of substance behavior in strongly nonequilibrium conditions. Using medical terminology, one could say, that tomographic diagnostics of the equilibrium plasma sources studies their ``anatomic'' structure, while reconstruction of the nonequilibrium plasma is similar to the ``physiological'' examination: it is directed to study the physical mechanisms and processes. The present work is focused on nonthermal plasma research. The tomographic diagnostics is directed to study spatial structures formed in the gas discharge plasmas under the influence of electrical and gravitational fields. The ways of plasma ``self-organization'' in changing and extreme conditions are analyzed. The analysis has been made using some examples from our practical tomographic diagnostics of nonthermal plasma sources, such as low-pressure capacitive and inductive discharges. [0pt] [1] Denisova N. Plasma diagnostics using computed tomography method // IEEE Trans. Plasma Sci. 2009 37 4 502.
Numerical simulation of dusty plasmas
Winske, D.
The numerical simulation of physical processes in dusty plasmas is reviewed, with emphasis on recent results and unresolved issues. Three areas of research are discussed: grain charging, weak dust-plasma interactions, and strong dust-plasma interactions. For each area, we review the basic concepts that are tested by simulations, present some appropriate examples, and examine numerical issues associated with extending present work.
High-temperature plasma physics
Furth, H.P.
Both magnetic and inertial confinement research are entering the plasma parameter range of fusion reactor interest. This paper reviews the individual and common technical problems of these two approaches to the generation of thermonuclear plasmas, and describes some related applications of high-temperature plasma physics.
Plasma chemistry and its applications
NASA Technical Reports Server (NTRS)
Hozumi, K.
The relationship between discharge phenomena and plasma chemistry, as well as the equipment and mechanisms of plasma chemical reactions are described. Various areas in which plasma chemistry is applied are surveyed, such as: manufacturing of semiconductor integrated circuits; synthetic fibers; high polymer materials for medical uses; optical lenses; and membrane filters (reverse penetration films).
Gas-discharge plasma sources for nonlocal plasma technology
Demidov, V. I.; DeJoseph, C. A. Jr.; Simonov, V. Ya.
Nonlocal plasma technology is based on the effect of self-trapping of fast electrons in the plasma volume [V. I. Demidov, C. A. DeJoseph, Jr., and A. A. Kudryavtsev, Phys. Rev. Lett. 95, 215002 (2006)]. This effect can be achieved by changing the ratio of fast electron flux to ion flux incident on the plasma boundaries. This in turn leads to a significant change in plasma properties and therefore can be useful for technological applications. A gas-discharge device which demonstrates control of the plasma properties by this method is described.
High beta plasma operation in a toroidal plasma producing device
Clarke, John F.
A high beta plasma is produced in a plasma producing device of toroidal configuration by ohmic heating and auxiliary heating. The plasma pressure is continuously monitored and used in a control system to program the current in the poloidal field windings. Throughout the heating process, magnetic flux is conserved inside the plasma and the distortion of the flux surfaces drives a current in the plasma. As a consequence, the total current increases and the poloidal field windings are driven with an equal and opposing increasing current. The spatial distribution of the current in the poloidal field windings is determined by the plasma pressure. Plasma equilibrium is maintained thereby, and high temperature, high beta operation results.
Amplification of Beam Acceleration in a Plasma by Plasma Instability
Valeri Lebedev
Although achieving of high accelerating field in a plasma has been demonstrated experimentally, a practical use of such a scheme for building a large accelerator is questionable. A novel scheme of beam acceleration by a plasma wave is considered in this article. The scheme is based on an initial excitation of a plasma wave by a probe beam with comparatively modest intensity. This seed excitation is then amplified by plasma instability, so that the test beam which follows the probe beam with a small delay will be accelerated by the plasma wave with an amplitude significantly exceeding the initial amplitude of the wave. Because of small interaction between the synchronization beam and the plasma, such a scheme allows one to excite a plasma over large length and, consequently, to build a large accelerator.
MHD Simulations of Thermal Plasma Jets in Coaxial Plasma Accelerators
NASA Astrophysics Data System (ADS)
Subramaniam, Vivek; Raja, Laxminarayan
The development of a magneto-hydrodynamics (MHD) numerical tool to study high energy density thermal plasma in coaxial plasma accelerators is presented. The coaxial plasma accelerator is a device used simulate the conditions created at the confining wall of a thermonuclear fusion reactor during an edge localized mode (ELM) disruption event. This is achieved by creating magnetized thermal plasma in a coaxial volume which is then accelerated by the Lorentz force to form a high velocity plasma jet. The simulation tool developed solves the resistive MHD equation using a finite volume method (FVM) framework. The acceleration and subsequent demagnetization of the plasma as it travels down the length of the accelerator is simulated and shows good agreement with experiments. Additionally, a model to study the thermalization of the plasma at the inlet is being developed in order to give self-consistent initial conditions to the MHD solver.
Dense Plasma Injectors for the HyperV Plasma Jets
NASA Astrophysics Data System (ADS)
Witherspoon, F. Douglas; Bomgardner, Richard; Case, Andrew; Messer, Sarah; Brockington, Samuel
HyperV is developing high velocity dense plasma jets for application to fusion and HEDP. The approach uses symmetric pulsed injection of high density plasma into a coaxial EM accelerator having a cross-section tailored to prevent formation of the blow-by instability. Work to date has focused on injection using ablative plasma sources, such as capillaries and sparkgaps, but injection of pure plasma, such as D and T, or high-Z gases such as Argon, require a different approach. We describe experiments and diagnostic measurements to develop small parallel plate railguns (MiniRailguns) to generate high density plasma pulses for injection into the coax gun. We also present a brief update of latest results from the 112 electrode sparkgap gun and the 64 capillary TwoPi plasma jet merging experiment, both of which have been upgraded with higher energy pulse forming networks to double the mass of ablatively injected plasma.
Pulsed Electromagnetic Acceleration of Plasmas
NASA Technical Reports Server (NTRS)
Thio, Y. C. Francis; Cassibry, Jason T.; Markusic, Tom E.; Rodgers, Stephen L. (Technical Monitor)
A major shift in paradigm in driving pulsed plasma thruster is necessary if the original goal of accelerating a plasma sheet efficiently to high velocities as a plasma "slug" is to be realized. Firstly, the plasma interior needs to be highly collisional so that it can be dammed by the plasma edge layer not (upstream) adjacent to the driving 'vacuum' magnetic field. Secondly, the plasma edge layer needs to be strongly magnetized so that its Hall parameter is of the order of unity in this region to ensure excellent coupling of the Lorentz force to the plasma. Thirdly, to prevent and/or suppress the occurrence of secondary arcs or restrike behind the plasma, the region behind the plasma needs to be collisionless and extremely magnetized with sufficiently large Hall parameter. This places a vacuum requirement on the bore conditions prior to the shot. These requirements are quantified in the paper and lead to the introduction of three new design parameters corresponding to these three plasma requirements. The first parameter, labeled in the paper as gamma (sub 1), pertains to the permissible ratio of the diffusive excursion of the plasma during the course of the acceleration to the plasma longitudinal dimension. The second parameter is the required Hall parameter of the edge plasma region, and the third parameter the required Hall parameter of the region behind the plasma. Experimental research is required to quantify the values of these design parameters. Based upon fundamental theory of the transport processes in plasma, some theoretical guidance on the choice of these parameters are provided to help designing the necessary experiments to acquire these data.
Plasma chemistry for inorganic materials
NASA Technical Reports Server (NTRS)
Matsumoto, O.
Practical application of plasma chemistry to the development of inorganic materials using both low temperature and warm plasmas are summarized. Topics cover: the surface nitrification and oxidation of metals; chemical vapor deposition; formation of minute oxide particles; the composition of oxides from chloride vapor; the composition of carbides and nitrides; freezing high temperature phases by plasma arc welding and plasma jet; use of plasma in the development of a substitute for petroleum; the production of silicon for use in solar cell batteries; and insulating the inner surface of nuclear fusion reactor walls.
Closed inductively coupled plasma cell
Manning, T.J.; Palmer, B.A.; Hof, D.E.
A closed inductively coupled plasma cell generates a relatively high power, low noise plasma for use in spectroscopic studies is disclosed. A variety of gases can be selected to form the plasma to minimize spectroscopic interference and to provide a electron density and temperature range for the sample to be analyzed. Grounded conductors are placed at the tube ends and axially displaced from the inductive coil, whereby the resulting electromagnetic field acts to elongate the plasma in the tube. Sample materials can be injected in the plasma to be excited for spectroscopy. 1 fig.
Closed inductively coupled plasma cell
Manning, Thomas J.; Palmer, Byron A.; Hof, Douglas E.
A closed inductively coupled plasma cell generates a relatively high power, low noise plasma for use in spectroscopic studies. A variety of gases can be selected to form the plasma to minimize spectroscopic interference and to provide a electron density and temperature range for the sample to be analyzed. Grounded conductors are placed at the tube ends and axially displaced from the inductive coil, whereby the resulting electromagnetic field acts to elongate the plasma in the tube. Sample materials can be injected in the plasma to be excited for spectroscopy.
Plasmas in the earth's magnetotail
NASA Technical Reports Server (NTRS)
Frank, L. A.
An overview of the general charcteristics of plasmas within the earth's magnetotail and its environs is presented. Present knowledge of the plasma within these regions as gained via in situ measurements provides the general theme, although observations of magnetic fields, energetic particles and plasma waves are included in the discussion. Primary plasma regimes in the magnetotail are the plasma sheet, its boundary layer, the magnetotail lobes, the boundary layer at the magnetopause and the distant magnetotail. Although great progress in the understanding of these regions is evident in the literature of the past several years, many of their features remain as exciting enigmas to be resolved by future observational and theoretical investigation.
Experimental Plasma Research project summaries
This report contains descriptions of the activities supported by the Experimental Plasma Research Branch of APP. The individual project summaries were prepared by the principal investigators and include objectives and milestones for each project. The projects are arranged in six research categories: Plasma Properties; Plasma Heating; Plasma Diagnostics; Atomic, Molecular and Nuclear Physics; Advanced Superconducting Materials; and the Fusion Plasma Research Facility (FPRF). Each category is introduced with a statement of objectives and recent progress and followed by descriptions of individual projects. An overall budget summary is provided at the beginning of the report.
Plasma afterburners and related issues
NASA Astrophysics Data System (ADS)
Huang, Chengkun
In plasma wakefield acceleration experiments, the drive beam moves at the speed of light in the plasma and excites an accelerating plasma wakefield behind the driver. Therefore it is possible to use a trailing electron beam to extract energy from the plasma wave wake. Such a design, called the plasma afterburner, has been proposed to double the energy of the incoming beam train for a future linear collider. We investigate the nonlinear beam-plasma interaction in such scenario using a 3D computer modeling code, QuickPIC. We will report on the simulation results of a 1 TeV plasma afterburner design. Several issues such as efficient beam-loading and the stability of the beam in the plasma are also analyzed. The electron hosing instability in the blow-out regime of plasma wakefield acceleration is also investigated using linear perturbation theory upon the electron blow-out trajectory. The growth of the hosing instability is found to be affected by the plasma self-fields, the relativistic mass, the axial motion of plasma electrons and the position-dependent ion channel radius respectively. Therefore the hosing growth has dependence on the beam current, which is not found in the fluid theory. PIC simulations agree very well with this new theory.
Transport processes in space plasmas
Birn, J.; Elphic, R.C.; Feldman, W.C.
This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project represents a comprehensive research effort to study plasma and field transport processes relevant for solar-terrestrial interaction, involving the solar wind and imbedded magnetic field and plasma structures, the bow shock of the Earth`s magnetosphere and associated waves, the Earth`s magnetopause with imbedded flux rope structures and their connection with the Earth, plasma flow in the Earth`s magnetotail, and ionospheric beam/wave interactions. The focus of the work was on the interaction between plasma and magnetic and electric fields in the regions where different plasma populations exist adjacent to or superposed on each other. These are the regions of particularly dynamic plasma behavior, important for plasma and energy transport and rapid energy releases. The research addressed questions about how this interaction takes place, what waves, instabilities, and particle/field interactions are involved, how the penetration of plasma and energy through characteristic boundaries takes place, and how the characteristic properties of the plasmas and fields of the different populations influence each other on different spatial and temporal scales. These topics were investigated through combining efforts in the analysis of plasma and field data obtained through space missions with theory and computer simulations of the plasma behavior.
Space plasma contractor research, 1988
NASA Technical Reports Server (NTRS)
Williams, John D.; Wilbur, Paul J.
Results of experiments conducted on hollow cathode-based plasma contractors are reported. Specific tests in which attempts were made to vary plasma conditions in the simulated ionospheric plasma are described. Experimental results showing the effects of contractor flowrate and ion collecting surface size on contactor performance and contactor plasma plume geometry are presented. In addition to this work, one-dimensional solutions to spherical and cylindircal space-charge limited double-sheath problems are developed. A technique is proposed that can be used to apply these solutions to the problem of current flow through elongated double-sheaths that separate two cold plasmas. Two conference papers which describe the essential features of the plasma contacting process and present data that should facilitate calibration of comprehensive numerical models of the plasma contacting process are also included.
Main Features of Plasma Control
Crisanti, F.; Albanese, R.; Ambrosino, G.
In the recent years Plasma Control has always increased his importance in any advanced experiment. It is now clear that ITER will not be able to operate without a quite advanced and sophisticated control apparatus. Necessarily this system will have to integrate several different aspects of the Plasma behavior. One of the most important parts of a closed loop control system is the quality of the measurement of the plasma parameters that should be controlled. Eventually, this aspect involves sophisticated and complex diagnostic apparatus. This paper presents an overview of the present status, and further studies and developments needed, in the next future, for the design and realization of an integrated plasma control system aimed at both stabilizing the plasma non-axisymmetric instabilities and controlling the most important internal plasma parameters. In particular the Edge Localized Modes (ELMs), the Neo-Classical Tearing Modes (NTM), the Resistive Wall Mode (RWM) and the Plasma Profiles control system necessities will be shortly illustrated.
Axially Modulated Plasma Waveguides
Layer, B. D.; York, A. G.; Varma, S.; Chen, Y.-H.; Milchberg, H. M.
We demonstrate two techniques for making periodically modulated plasma waveguides-one with sharp, stable voids as short as 50 {mu}m with a period as small as 200 {mu}m, and another which modulates the waveguide diameter with a corrugation period as short as 35 {mu}m[1]. These features persist as the plasma expands for the full lifetime of the waveguide (>6 ns). The waveguides were made using the hydrodynamic shock method in a cluster jet using hydrogen, nitrogen, and argon. We demonstrate guided propagation at intensities up to 2x10{sup 17} W/cm{sup 2}, limited by our laser energy currently available. This technique is useful for quasi-phase matching to allow efficient coupling of laser energy to acceleration of relativistic electrons or generation of coherent electromagnetic radiation at selected frequencies.
NASA Astrophysics Data System (ADS)
Ransom, C. J.
Z-pinch plasma simulations have been performed that indicate the production of spherules under certain experimental parameters. (A. L. Peratt, private communication) While performing experiments dealing with the impact of plasma discharges on various materials, we observed that spherules were created at the surface of some of the materials. For specific materials and conditions, spherules were always produced. Both individual spherules and joined spherules were created. The size and shapes were nearly identical to items found by the Mars rover, Opportunity, and called ``blueberries.'' Sky & Telescope, June 2004, p. 20, among other sources indicated the blueberries were gray spherules composed of hematite. The experiments produced hematite spherules identical in appearance to those found on Mars. These experiments suggest how the newly discovered blueberries were formed on Mars while providing an explanation that does not depend on the presence of water.
Plasma concentrations of benzodiazepines.
Bond, A J; Hailey, D M; Lader, M H
1. Twenty anxious patients were treated with medazepam, diazepam, chlordiazepoxide, amylobarbitone and placebo, each given in flexible dosage for 2-4 weeks. 2. At the end of each treatment, a series of clinical, physiological and behavioural variables were measured and plasma samples were taken for estimation of the appropriate drug and metabolite concentrations. 3. Nordiazepam was shown to be an important metabolite of both medazepam and diazepam: the ratio of medazepam to noradiazepam was 0.14 and the ratio of diazepam to nordiazepam following diazepam administration was 0.72. 4. No significant correlations were found between the plasma concentrations of any of the treatments and the clinical ratings or behavioural measures. 5. Some relationship was shown between levels of medazepam and its physiological effects. PMID:14659
Frazer, L
Thanks to a series of joint research projects by Los Alamos National Laboratory, Beta Squared of Allen, Texas, and the University of California at Los Angeles, there is now a more environmentally sound method for cleaning semiconductor chips that may also be effective in cleaning up chemical, bacterial, and nuclear contaminants. The Atmospheric Pressure Plasma Jet uses a type of ionized gas called plasma to clean up contaminants by binding to them and lifting them away. In contrast to the corrosive acids and chemical solvents traditionally used to clean semiconductor chips, the jet oxidizes contaminants, producing only benign gaseous by-products such as oxygen and carbon dioxide. The new technology is also easy to transport, cleans thoroughly and quickly, and presents no hazards to its operators. PMID:10417375
Plasma and magnetospheric research
NASA Technical Reports Server (NTRS)
Comfort, R. H.; Horwitz, J. L.
Several programs and variations have been developed to determine statistical means of different plasma parameters when binned in different variables. These parameters include temperature, densities and spacecraft potentials for any of the ion species, as well as ratios of these variables for any other ion species to the corresponding variable for H(+). The variables for binning include L, radial distance, and geomagnetic latitude; and separate statistics are automatically run for local morning and local evening data. These programs all run from output files from the plasma parameter thin sheath analysis program. A variant program also bins for magnetic activity, using either Kp or Dst, which requires an additional magnetic activity input file. These programs can be run either interactively or in batch mode, using file listings generated by a DIRECTORY command. In addition to printed output, these programs generate output files which can be used to plot the results. Programs to plot these averaged data are under development.
Hopkins, Matthew Morgan; DeChant, Lawrence Justin.; Piekos, Edward Stanley; Pointon, Timothy David
This report summarizes the work completed during FY2007 and FY2008 for the LDRD project ''Hybrid Plasma Modeling''. The goal of this project was to develop hybrid methods to model plasmas across the non-continuum-to-continuum collisionality spectrum. The primary methodology to span these regimes was to couple a kinetic method (e.g., Particle-In-Cell) in the non-continuum regions to a continuum PDE-based method (e.g., finite differences) in continuum regions. The interface between the two would be adjusted dynamically ased on statistical sampling of the kinetic results. Although originally a three-year project, it became clear during the second year (FY2008) that there were not sufficient resources to complete the project and it was terminated mid-year.
Equatorially trapped plasma populations
NASA Technical Reports Server (NTRS)
Olsen, R. C.
The SCATHA observations of the equatorially trapped plasmas are presented in order to emphasize the importance of making measurements at the equator. The UCSD plasma detector and the GSFC electric field experiment are described, as are the pertinent characteristics of the magnetometer and mass spectrometers. The electron distribution reveals a width of 20 deg to 60 deg, narrowing with increasing energy. The 20- to 100-eV ion fluxes typically exhibit temperatures in the 20to 50-eV range and densities of 1-10 per cu cm. The electron population typically ranges from 50 to 500 eV, with temperatures of 100-200 eV and densities also in the 1-10 per cu cm range. Field-aligned populations of lower energy are occasionally found in both ions and electrons at the same location.
Dust interferometers in plasmas
NASA Astrophysics Data System (ADS)
Chaudhuri, M.; Nosenko, V.; Thomas, H. M.
An interferometric imaging technique has been proposed to instantly measure the diameter of individual spherical dust particles suspended in a gas discharge plasma. The technique is based on the defocused image analysis of both spherical particles and their binary agglomerates. Above a critical diameter, the defocused images of spherical particles contain stationary interference fringe patterns and the fringe number increases with particle diameters. Below this critical diameter, the particle size has been measured using the rotational interference fringe patterns which appear only on the defocused images of binary agglomerates. In this case, a lower cutoff limit of particle diameter has been predicted, below which no such rotational fringe patterns are observed for the binary agglomerates. The method can be useful as a diagnostics for complex plasma experiments on earth as well as under microgravity conditions.
Cosmic Plasma Wakefield Acceleration
NASA Astrophysics Data System (ADS)
Chen, Pisin; Tajima, Toshiki; Takahashi, Yoshiyuki
A cosmic acceleration mechanism is introduced which is based on the wakefields excited by the Alfven shocks in a relativistically flowing plasma. We show that there exists a threshold condition for transparency below which the accelerating particle is collision-free and suffers little energy loss in the plasma medium. The stochastic encounters of the random accelerating-decelerating phases results in a power-law energy spectrum: f([epsilon]) [is proportional to] 1/[epsilon]2. As an example, we discuss the possible production of super-GZK ultra high energy cosmic rays (UHECR) in the atmosphere of gamma ray bursts. The estimated event rate in our model agrees with that from UHECR observations. [copyright] 2002 American Institute of Physics
Potentials of fissioning plasmas
NASA Technical Reports Server (NTRS)
Thom, K.
Successful experiments with the nuclear pumping of lasers have demonstrated that in a gaseous medium the kinetic energy of fission fragments can be converted directly into nonequilibrium optical radiation. This confirms the concept that the fissioning medium in a gas-phase nuclear reactor shows an internal structure such as a plasma in near thermal equilibrium varying up to a state of extreme nonequilibrium. During 20 years of research under NASA support major elements of the fissioning plasma reactor were demonstrated in theory and experiment, culminating in a proof-of-principle reactor test conducted at the Los Alamos Scientific Laboratory. It is concluded that the construction of a gaseous fuel reactor power plant is within the reach of present technology.
Io Plasma Torus: Nature of the Iogenic Plasma Source
NASA Astrophysics Data System (ADS)
Marconi, M. L.; Smyth, W. H.
The primary source of plasma for Jupiter's magnetosphere is supplied internally by Io, the innermost Galilean satellite. The Iogenic plasma source is created by gases (e.g., Na, K, O, S, and SO_2) lost from Io as they undergo electron impact and charge exchange reactions in the plasma torus. This Iogenic plasma source provides mass, momentum, pick-up electrical conductivity, and energy to the plasma torus. The three-dimensional nature of the Iogenic plasma source is an important input quantity (1) in local studies to understand the plasma torus properties (density, composition, subcorotational motion, electric currents, and temperature) and the plasma torus near-Io MHD flow and atmosphere interactions, and (2) in more global studies to understand the spacetime structure of the outward transport dynamics of the plasma torus, such as in RCM-J (Rice Convection Model for Jupiter) calculations. To elucidate and quantify the nature of the Iogenic plasma source for such studies, we have undertaken simulations of it using the AER neutral cloud models. Calculations will be presented to illustrate the spacetime nature of the Iogenic plasma source and to estimate the net-mass, momentum and energy input rates to the plasma torus and the height-integrated electrical conductivity near Io and in Jupiter's ionosphere. These calculations show that the instantaneous Iogenic plasma source is highly peaked at Io's position in the plasma torus and that its rates vary significantly with Io System III longitude and also with Io phase angle because of the east-west electric field. For the lower-velocity escape of gases by incomplete collisional cascade processes (i.e., plasma torus ion sputtering), contributions to the instantaneous Iogenic plasma source are primarily confined to a broader (but still limited) spatial region in L-shell and System III longitude angle near Io. For the higher-velocity loss of gases by charge exchange, contributions to the Iogenic plasma source are more
Brodin, G.; Marklund, M.; Zamanian, J.
A fluid model is derived, taking into account the effect of spin magnetization of electrons as well as of magnetized dust grains. The model is analyzed, and it is found that both the acoustic velocity and the Alfven velocity is decreased due to the magnetization effects. Furthermore, for low-temperature high density plasmas, it is found that the linear wave modes can be unstable, due to the magnetic attraction of individual fluid elements. The significance of our results are discussed.
On neutral plasma oscillations
Shadwick, B.A.; Morrison, P.J.
We examine the conditions for the existence of spectrally stable neutral modes in a Vlasov-Poisson plasma and show that for stable equilibria of systems that have unbounded spatial domain, the only possible neutral modes are those with phase velocities that correspond to stationary inflection points of the equilibrium distribution function. It is seen that these neutral modes can possess positive or negative free energy.
Bharatia, Pravin R.; Pradhan, Avinash M.; Zawar, Vijay P.
Plasma cell vulvitis is a very rare inflammatory disorder of vulva, characterized by a bright-red mucosal lesion of significant chronicity, which may be symptomatic. Very few case studies of this condition are reported in literature. We describe one such classical patient, who presented with slight dyspareunia. The diagnosis was confirmed on histopathological examination. It is important for clinicians to accurately diagnose this alarming condition in time. PMID:26692614
Princeton Plasma Physics Laboratory:
Phillips, C.A.
This paper discusses progress on experiments at the Princeton Plasma Physics Laboratory. The projects and areas discussed are: Principal Parameters Achieved in Experimental Devices, Tokamak Fusion Test Reactor, Princeton Large Torus, Princeton Beta Experiment, S-1 Spheromak, Current-Drive Experiment, X-ray Laser Studies, Theoretical Division, Tokamak Modeling, Spacecraft Glow Experiment, Compact Ignition Tokamak, Engineering Department, Project Planning and Safety Office, Quality Assurance and Reliability, and Administrative Operations.
Cairns, R. A.; Vorgul, I.; Bingham, R.; Ronald, K.; Speirs, D. C.; Phelps, A. D. R.; McConville, S. L.; Gillespie, K. M.; Cross, A. W.; Robertson, C. W.; Whyte, C. G.; Kellett, B. J.
We describe the theory of a cyclotron maser instability which appears to be a likely source of auroral kilometric radiation and its generation in a laboratory experiment. We then outline plans for future development of the experiment to investigate a wider range of instabilities resulting from the existence of electron beams in a plasma. The basic theory theory underlying a few of these is then discussed.
Spectroscopy of divertor plasmas
Isler, R.C.
The requirements for divertor spectroscopy are treated with respect to instrumentation and observations on present machines. Emphasis is placed on quantitative measurements.of impurity concentrations from the interpretation of spectral line intensities. The possible influence of non-Maxwellian electron distributions on spectral line excitation in the divertor is discussed. Finally the use of spectroscopy for determining plasma temperature, density, and flows is examined.
Filamentary magnetohydrodynamic plasmas
NASA Astrophysics Data System (ADS)
Kinney, R.; Tajima, T.; McWilliams, J. C.; Petviashvili, N.
A filamentary construct of magnetohydrodynamical plasma dynamics based on the Elsässer variables is developed. This approach is modeled after discrete vortex models of hydrodynamical turbulence, which cannot be expected in general to produce results identical to those based on a Fourier decomposition of the fields. In a highly intermittent plasma, the induction force is small compared to the convective motion, and when this force is neglected, the plasma vortex system is described by a Hamiltonian. A statistical treatment of a collection of discrete current-vorticity concentrations is given. Canonical and microcanonical statistical calculations show that both the vorticity and the current spectra are peaked at long wavelengths, and the expected states revert to known hydrodynamical states as the magnetic field vanishes. These results differ from previous Fourier-based statistical theories, but it is found that when the filament calculation is expanded to include the inductive force, the results approach the Fourier equilibria in the low-temperature limit, and the previous Hamiltonian plasma vortex results in the high-temperature limit. Numerical simulations of a large number of filaments are carried out and support the theory. A three-dimensional vortex model is presented as well, which is also Hamiltonian when the inductive force is neglected. A statistical calculation in the canonical ensemble and numerical simulations show that a nonzero large-scale magnetic field is statistically favored, and that the preferred shape of this field is a long, thin tube of flux. Possible applications to a variety of physical phenomena are suggested.
NASA Astrophysics Data System (ADS)
Schukla, Padma K.; Stenflo, Lennart; Eliasson, Bengt
Nonlinear collective processes in very dense plasmas / P. K. Shukla, B. Eliasson and D. Shaikh -- Quantum, spin and QED effects in plasmas / G. Brodin and M. Marklund -- Spin quantum plasmas - new aspects of collective dynamics / M. Marklund and G. Brodin -- Revised quantum electrodynamics with fundamental applications / B. Lehnert -- Quantum methodologies in beam, fluid and plasma physics / R. Fedele -- Plasma effects in cold atom physics / J. T. Mendonca ... [et al.] -- General properties of the Rayleigh-Taylor instability in different plasma configurations: the plasma foil model / F. Pegoraro and S. V. Bulanov -- The Rayleigh-Taylor instability of a plasma foil accelerated by the radiation pressure of an ultra intense laser pulse / F. Pegoraro and S. V. Bulanov -- Generation of galactic seed magnetic fields / H. Saleem -- Nonlinear dynamics of mirror waves in non-Maxwellian plasmas / O. A. Pokhotelov et al. -- Formation of mirror structures near instability threshold / E. A. Kuznetsov, T. Passot and P. L. Sulem -- Nonlinear dispersive Alfvén waves in magnetoplasmas / P. K. Shukla ... [et al.] -- Properties of drift and Alfvén waves in collisional plasmas / J. Vranjes, S. Poedts and B. P. Pandey -- Current driven acoustic perturbations in partially ionized collisional plasmas / J. Vranjes ... [et al.] -- Multifluid theory of solitons / F. Verheest -- Nonlinear wavepackets in pair-ion and electron-positron-ion plasmas / I. Kourakis et al. -- Electro-acoustic solitary waves in dusty plasmas / A. A. Mamun and P. K. Shukla -- Physics of dust in magnetic fusion devices / Z. Wang et al. -- Short wavelength ballooning mode in Tokamaks / A. Hirose and N. Joiner -- Effects of perpendicular shear superposition and hybrid ions intruduction on parallel shear driven plasma instabilities / T. Kaneko and R. Hatakeyama.
Momentum transfer to rotating magnetized plasma from gun plasma injection
Shamim, Imran; Hassam, A. B.; Ellis, R. F.; Witherspoon, F. D.; Phillips, M. W.
Numerical simulations are carried out to investigate the penetration and momentum coupling of a gun-injected plasma slug into a rotating magnetized plasma. An experiment along these lines is envisioned for the Maryland Centrifugal Experiment (MCX) [R. F. Ellis et al., Phys. Plasmas 8, 2057 (2001)] using a coaxial plasma accelerator gun developed by HyperV Technologies Corp. [F. D. Witherspoon et al., Bull. Am. Phys. Soc. 50, LP1 87 (2005)]. The plasma gun would be located in the axial midplane and fired off-axis into the rotating MCX plasma annulus. The numerical simulation is set up so that the initial momentum in the injected plasma slug is of the order of the initial momentum of the target plasma. Several numerical firings are done into the cylindrical rotating plasma. Axial symmetry is assumed. The slug is seen to penetrate readily and deform into a mushroom, characteristic of interchange deformations. It is found that up to 25% of the momentum in the slug can be transferred to the background plasma in one pass across a cylindrical chord. For the same initial momentum, a high-speed low density slug gives more momentum transfer than a low-speed high density slug. Details of the numerical simulations and a scaling study are presented.
Plasma probe characteristics in low density hydrogen pulsed plasmas
NASA Astrophysics Data System (ADS)
Astakhov, D. I.; Goedheer, W. J.; Lee, C. J.; Ivanov, V. V.; Krivtsun, V. M.; Zotovich, A. I.; Zyryanov, S. M.; Lopaev, D. V.; Bijkerk, F.
Probe theories are only applicable in the regime where the probe's perturbation of the plasma can be neglected. However, it is not always possible to know, a priori, that a particular probe theory can be successfully applied, especially in low density plasmas. This is especially difficult in the case of transient, low density plasmas. Here, we applied probe diagnostics in combination with a 2D particle-in-cell model, to an experiment with a pulsed low density hydrogen plasma. The calculations took into account the full chamber geometry, including the plasma probe as an electrode in the chamber. It was found that the simulations reproduce the time evolution of the probe IV characteristics with good accuracy. The disagreement between the simulated and probe measured plasma density is attributed to the limited applicability of probe theory to measurements of low density pulsed plasmas on a similarly short time scale as investigated here. Indeed, in the case studied here, probe measurements would lead to, either a large overestimate, or underestimate of the plasma density, depending on the chosen probe theory. In contrast, the simulations of the plasma evolution and the probe characteristics do not suffer from such strict applicability limits. These studies show that probe theory cannot be justified through probe measurements. However, limiting cases of probe theories can be used to estimate upper and lower bounds on plasma densities. These theories include and neglect orbital motion, respectively, with different collisional terms leading to intermediate estimates.
Plasma Torch for Plasma Ignition and Combustion of Coal
NASA Astrophysics Data System (ADS)
Ustimenko, Alexandr; Messerle, Vladimir
Plasma-fuel systems (PFS) have been developed to improve coal combustion efficiency. PFS is a pulverized coal burner equipped with arc plasma torch producing high temperature air stream of 4000 - 6000 K. Plasma activation of coal at the PFS increases the coal reactivity and provides more effective ignition and ecologically friendly incineration of low-rank coal. The main and crucial element of PFS is plasma torch. Simplicity and reliability of the industrial arc plasma torches using cylindrical copper cathode and air as plasma forming gas predestined their application at heat and power engineering for plasma aided coal combustion. Life time of these plasma torches electrodes is critical and usually limited to 200 hours. Considered in this report direct current arc plasma torch has the cathode life significantly exceeded 1000 hours. To ensure the electrodes long life the process of hydrocarbon gas dissociation in the electric arc discharge is used. In accordance to this method atoms and ions of carbon from near-electrode plasma deposit on the active surface of the electrodes and form electrode carbon condensate which operates as ``actual'' electrode. Complex physicochemical investigation showed that deposit consists of nanocarbon material.
Linking plasma kinetics to plasma-bio interactions
NASA Astrophysics Data System (ADS)
Bruggeman, Peter
Cold non-equilibrium atmospheric pressure plasmas have received a lot of attention in the last decade due to their huge potential for biomedical applications. In my group, we have characterized an RF driven APPJ in great detail. The characterization includes electrical measurements, imaging, optical emission spectroscopy, (two photon enhanced) laser induced fluorescence, Thomson scattering, Rayleigh scattering, Raman scattering and mass spectrometry. This led to a detailed knowledge of the electron density, electron temperature, gas temperature, NO, O, OH, O3 densities, ionic species and air concentrations in the plasma effluent. Living organisms for in vitro studies are typically kept in complex solutions or culture media. Plasma-bio interactions involves not only the production of reactive species in the plasma gas phase but also transport to the liquid phase and plasma induced liquid phase chemistry and its impact on the living organisms. Reactive nitrogen and oxygen species have been identified as the key reactive species. Recent results of my group show that controlling the gas phase plasma chemistry can lead to significant different biological responses of the living organisms corresponding to different chemical pathways. The effect of plasma jet interaction with liquids containing mammalian cells, bacteria and virus will be discussed. The outcomes of these studies allow unraveling chemical pathways responsible for plasma-bio interactions and linking plasma kinetics to plasma-bio interactions.
Momentum transfer to rotating magnetized plasma from gun plasma injection
NASA Astrophysics Data System (ADS)
Shamim, Imran; Hassam, A. B.; Ellis, R. F.; Witherspoon, F. D.; Phillips, M. W.
Numerical simulations are carried out to investigate the penetration and momentum coupling of a gun-injected plasma slug into a rotating magnetized plasma. An experiment along these lines is envisioned for the Maryland Centrifugal Experiment (MCX) [R. F. Ellis et al., Phys. Plasmas 8, 2057 (2001)] using a coaxial plasma accelerator gun developed by HyperV Technologies Corp. [F. D. Witherspoon et al., Bull. Am. Phys. Soc. 50, LP1-87 (2005)]. The plasma gun would be located in the axial midplane and fired off-axis into the rotating MCX plasma annulus. The numerical simulation is set up so that the initial momentum in the injected plasma slug is of the order of the initial momentum of the target plasma. Several numerical firings are done into the cylindrical rotating plasma. Axial symmetry is assumed. The slug is seen to penetrate readily and deform into a mushroom, characteristic of interchange deformations. It is found that up to 25% of the momentum in the slug can be transferred to the background plasma in one pass across a cylindrical chord. For the same initial momentum, a high-speed low density slug gives more momentum transfer than a low-speed high density slug. Details of the numerical simulations and a scaling study are presented.
The Coalition for Plasma Science: Bringing Plasmas to the Public
NASA Astrophysics Data System (ADS)
Berry, Lee
The Coalition for Plasma Science is a group of institutions, organizations, and companies that have joined forces to increase awareness and understanding of plasma science and its many applications and benefits for society. The CPS undertakes a range of activities to support this goal. Members include national laboratories, universities, industries, and individuals. The CPS maintains a web page (http://www.plasmacoalition.org), and has developed several types of plasma-related publications. The web page includes a compilation of evaluated plasma web sites. The evaluations were conducted by teachers and based on national teaching standards. The web site also contains copies of CPS publications including the brochure ''Plasmas are Everywhere.'' Thousands of these brochures are distributed each year, and a poster version is now available. Another publication is the ''About Plasmas'' series. Each of these two-page papers (which is written for a general audience) is about a specific plasma-related topic, such as lighting, fusion, space plasmas and plasma decontamination of biological hazards. Papers on other topics are under development. The CPS also organizes educational luncheon/seminars for Members of Congress and their staff. The most recent seminar was given by David Newman on January 28th of this year and was his ''state of the universe'' address. A second seminar is planned this year on the topic of semiconductor manufacturing. Activities under discussion include a topical science fair award for a project on plasmas and the development of a broad, history-based educational web site.
Plasma Properties of Microwave Produced Plasma in a Toroidal Device
NASA Astrophysics Data System (ADS)
Singh, Ajay; Edwards, W. F.; Held, Eric
We have modified a small tokamak, STOR-1M, on loan from University of Saskatchewan, to operate as a low-temperature (~5 eV) toroidal plasma machine with externally induced toroidal magnetic fields ranging from zero to ~50 G. The plasma is produced using microwave discharges at relatively high pressures. Microwaves are produced by a kitchen microwave-oven magnetron operating at 2.45 GHz in continuous operating mode, resulting in pulses ~0.5 s in duration. Initial measurements of plasma formation in this device with and without applied magnetic fields are presented. Plasma density and temperature profiles have been measured using Langmuir probes and the magnetic field profile inside the plasma has been obtained using Hall probes. When the discharge is created with no applied toroidal magnetic field, the plasma does not fill the entire torus due to high background pressure. However, when a toroidal magnetic field is applied, the plasma flows along the applied field, filling the torus. Increasing the applied magnetic field seems to aid plasma formation - the peak density increases and the density gradient becomes steeper. Above a threshold magnetic field, the plasma develops low-frequency density oscillations due to probable excitation of flute modes in the plasma.
Radially inhomogeneous bounded plasmas
NASA Astrophysics Data System (ADS)
Zakeri-Khatir, H.; Aghamir, F. M.
On the basis of kinetic theory along with self-consistent field equations, the expressions for dielectric tensor of radially inhomogeneous magnetized plasma columns are obtained. The study of dielectric tensor characteristics allows the accurate analysis of the inhomogeneous properties, beyond limitations that exist in the conventional method. Through the Bessel–Fourier transformation, the localized form of material equations in a radially inhomogeneous medium are obtained. In order to verify the integrity of the model and reveal the effect of inhomogeneity, a special case of a cylindrical plasma waveguide completely filled with inhomogeneous magnetized cold plasma was considered. The dispersion relation curves for four families of electromagnetic (EH and HE) and electrostatic (SC and C) modes are obtained and compared with the findings of the conventional model. The numerical analysis indicates that the inhomogeneity effect leads to coupling of electromagnetic and electrostatic modes each having different radial eigen numbers. The study also reveals that the electrostatic modes are more sensitive to inhomogeneous effects than the electromagnetic modes.
Plasma Modeling of Electrosurgery
NASA Astrophysics Data System (ADS)
Jensen, Scott; Friedrichs, Daniel; Gilbert, James; Park, Wounjhang; Maksimovic, Dragan
Electrosurgery is the use of high frequency alternating current (AC) to illicit a clinical response in tissue, such as cutting or cauterization. Power electronics converters have been demonstrated to generate the necessary output voltage and current for electrosurgery. The design goal of the converter is to regulate output power while supplying high frequency AC. The design is complicated by fast current and voltage transients that occur when the current travels through air in the form of an arc. To assist in designing a converter that maintains the desired output power during these transients, we have used the COMSOL Plasma Module to determine the output voltage and current characteristics during an arc. This plasma model, used in conjunction with linear circuit elements, allows the full electrosurgical system to be validated. Two models have been tested with the COMSOL Plasma Module. One is a four-species, four-reaction model based on the local field approximation technique. The second simulates the underlying air chemistry using 30 species, 151 chemical reactions, and a coupled electron energy distribution function. Experimental output voltage and current samples have been collected and compared to both models.
Plasma interaction with microbes
NASA Astrophysics Data System (ADS)
Laroussi, M.; Mendis, D. A.; Rosenberg, M.
The germicidal effects of a non-equilibrium atmospheric pressure plasma generated by a novel resistive barrier discharge on representatives of the two classes of bacteria (Gram-negative and Gram-positive) are discussed. The plasma exposure, while being lethal to both bacterial classes, also produced gross structural damage in the Gram-negative E. coli while none was observed in the more structurally robust Gram-positive Bacillus subtilis. An electrophysical process involving the role of the electrostatic tension on a charged body in a plasma is invoked to explain both observations. Since the efficacy of this electrophysical process depends not only on the tensile strength of the bacterial cell wall but also on its shape and texture, the need for more experimental studies, using a wide range of bacteria belonging to various morphological groups, is suggested. Ways to further test the validity of this electrophysical lysis mechanism for Gram-negative bacteria on one hand, and also to extend its operation to the more robust Gram-positive bacteria on the other, are suggested.
Sterilization by oxygen plasma
NASA Astrophysics Data System (ADS)
Moreira, Adir José; Mansano, Ronaldo Domingues; Andreoli Pinto, Terezinha de Jesus; Ruas, Ronaldo; Zambon, Luis da Silva; da Silva, Mônica Valero; Verdonck, Patrick Bernard
The use of polymeric medical devices has stimulated the development of new sterilization methods. The traditional techniques rely on ethylene oxide, but there are many questions concerning the carcinogenic properties of the ethylene oxide residues adsorbed on the materials after processing. Another common technique is the gamma irradiation process, but it is costly, its safe operation requires an isolated site and it also affects the bulk properties of the polymers. The use of a gas plasma is an elegant alternative sterilization technique. The plasma promotes an efficient inactivation of the micro-organisms, minimises the damage to the materials and presents very little danger for personnel and the environment. Pure oxygen reactive ion etching type of plasmas were applied to inactivate a biologic indicator, the Bacillus stearothermophilus, to confirm the efficiency of this process. The sterilization processes took a short time, in a few minutes the mortality was complete. In situ analysis of the micro-organisms' inactivating time was possible using emission spectrophotometry. The increase in the intensity of the 777.5 nm oxygen line shows the end of the oxidation of the biologic materials. The results were also observed and corroborated by scanning electron microscopy.
Screening Resonances In Plasmas
Winkler, P.
When it was suggested that a new recombination mechanism (Resonant Radiative Recombination (RRR)) which, based on very general physical arguments, should happen in dense plasmas and promises to provide useful information for the local temperature and density diagnostics of plasmas, they assumed the existence of screening resonances. For model potentials the existence of screening resonances has been demonstrated beyond reasonable doubt in a number of calculations. The key question, how well those potentials describe the dominant effects of a real plasma remains open. The relation of theoretical predictions to experimentally measurable effects is an important issue at the present stage of their research. In particular, RRR is expected to account for enhanced recombination rates of low energetic electrons with their ions, since the first stage is the resonant capture of a slow electron by an atom or ion. The mechanism that traps an electron is a combination of complicated many-body interactions of the ions and electrons. For clarity they start here, however, with a discussion in terms of local potential traps the shapes of which are determined predominantly and in an average way by two factors: the degree of screening present at the ionic site and the degree of short-range order in the immediate neighborhood of this ion.
Modeling electronegative plasma discharge
Lichtenberg, A.J.; Lieberman, M.A.
Macroscopic analytic models for a three-component electronegative gas discharge are developed. Assuming the negative ions to be in Boltzmann equilibrium, a positive ion ambipolar diffusion equation is derived. The discharge consists of an electronegative core and electropositive edges. The electron density in the core is nearly uniform, allowing a parabolic approximation to the plasma profile to be employed. The resulting equilibrium equations are solved analytically and matched to a constant mobility transport model of an electropositive edge plasma. The solutions are compared to a simulation of a parallel-plane r.f. driven oxygen plasma for p = 50 mTorr and n{sub eo}= 2.4 x 10{sup 15} m{sup -3}. The ratio {alpha}{sub o} of central negative ion density to electron density, and the electron temperature T{sub e}, found in the simulation, are in reasonable agreement with the values calculated from the model. The model is extended to: (1) low pressures, where a variable mobility model is used in the electropositive edge region; and (2) high {alpha}{sub o} in which the edge region disappears. The inclusion of a second positive ion species, which can be very important in describing electronegative discharges used for materials processing, is a possible extension of the model.
NASA Astrophysics Data System (ADS)
Felizardo, Edgar; Pencheva, Mariana; Benova, Evgenia; Dias, Fransisco; Tatarova, Elena
A theoretical and experimental investigation of a microwave (2.45 GHz) Argon plasma torch driven by a surface wave is presented. The theoretical model couples in a self-consistent way the wave electrodynamics and the electron and heavy particle kinetics. The set of coupled equations includes: Maxwell's equations, the electron Boltzmann equation, including electron-electron collisions, and the particle balance equations for electrons, excited atoms (4s, 4p, 3d, 5s, 5p, 4d, 6s), and atomic (Ar^+) and molecular ions (Ar2^+). The input parameters of the model are: gas pressure (760 Torr), plasma radius (R = 0.75 cm), dielectric permittivity (ɛd = 4.0) and tube thickness (d = 0.15 cm) as well as the measured axial profile of the gas temperature (3500 K - 1500 K). The latter was determined from measurements of the rotational temperature of the OH molecular band in the range 306 - 315 nm. Phase and amplitude sensitive recording provides the data for the axial wavenumber and wave attenuation coefficient. The wavenumber decreases along the generated plasma torch. The electron density (Ne) axial profile as determined from measurements of Hβ Stark broadening is in agreement with the theoretical one.
de Larrea, Carlos Fernandez; Kyle, Robert A.; Durie, Brian GM; Ludwig, Heinz; Usmani, Saad; Vesole, David H.; Hajek, Roman; Miguel, Jésus San; Sezer, Orhan; Sonneveld, Pieter; Kumar, Shaji K.; Mahindra, Anuj; Comenzo, Ray; Palumbo, Antonio; Mazumber, Amitabha; Anderson, Kenneth C.; Richardson, Paul G.; Badros, Ashraf Z.; Caers, Jo; Cavo, Michele; LeLeu, Xavier; Dimopoulos, Meletios A.; Chim, CS; Schots, Rik; Noeul, Amara; Fantl, Dorotea; Mellqvist, Ulf-Henrik; Landgren, Ola; Chanan-Khan, Asher; Moreau, Philippe; Fonseca, Rafael; Merlini, Giampaolo; Lahuerta, JJ; Bladé, Joan; Orlowski, Robert Z.; Shah, Jatin J.
Plasma cell leukemia (PCL) is a rare and aggressive variant of myeloma characterized by the presence of circulating plasma cells. It is classified as either primary PCL occurring at diagnosis or as secondary PCL in patients with relapsed/refractory myeloma. Primary PCL is a distinct clinic-pathologic entity with different cytogenetic and molecular findings. The clinical course is aggressive with short remissions and survival duration. The diagnosis is based upon the percentage (≥ 20%) and absolute number (≥ 2 × 10 9/L) of plasma cells in the peripheral blood. It is proposed that the thresholds for diagnosis be reexamined and consensus recommendations are made for diagnosis, as well as, response and progression criteria. Induction therapy needs to begin promptly and have high clinical activity leading to rapid disease control in an effort to minimize the risk of early death. Intensive chemotherapy regimens and bortezomib-based regimens are recommended followed by high-dose therapy with autologous stem-cell transplantation (HDT/ASCT) if feasible. Allogeneic transplantation can be considered in younger patients. Prospective multicenter studies are required to provide revised definitions and better understanding of the pathogenesis of PCL. PMID:23288300
Magnetically Induced Plasma Rotation and the Dense Plasma Focus
NASA Astrophysics Data System (ADS)
Witalis, E. A.
Fusion for Fission fuel breeding and other incentives for unconventional magnetic fusion research are introductorily mentioned. The design, operation and peculiar characteristics of dense plasma foci are briefly described with attention to their remarkable ion acceleration and plasma heating capabilities. Attempts for interpretations are reviewed, and a brief account is given for an explanation based on the concept of magnetically induced plasma rotation, recently derived in detail in this journal. Basically an ion acceleration mechanism of betraton character it describes in combination with a dynamic, generalized Bennett relation focus plasma characteristics like the polarity dependence, the current channel disruption, the axial ion beam formation and the prerequisites for the ensuing turbulent plasma dissipative stage. Fundamental differences with respect to mainline fusion research are emphasized, and some conjectures and proposals are presented as to the further development of plasma focus nuclear fusion or fission energy production.
Systematic study of plasma flow during plasma sheet thinnings
NASA Technical Reports Server (NTRS)
Lui, A. T. Y.; Frank, L. A.; Ackerson, K. L.; Meng, C.-I.; Akasofu, S.-I.
On the basis of a study of Imp 6 measurements of plasma flow, it is concluded that there is no clear indication of a predominance of tailward plasma flow beyond about X = -15 R sub E in the midnight sector of the plasma sheet during the expansive phase of a substorm. In fact, it is shown statistically that sunward plasma flow is more frequently observed in the midnight sector within about 30 R sub E from the earth than in any other direction during plasma sheet thinning at the substorm expansion. This result supports the conclusion that there is no definite evidence for the formation of a reconnection neutral line in the near-earth plasma sheet during most substorms.
Plasma generating apparatus for large area plasma processing
Tsai, C.C.; Gorbatkin, S.M.; Berry, L.A.
A plasma generating apparatus for plasma processing applications is based on a permanent magnet line-cusp plasma confinement chamber coupled to a compact single-coil microwave waveguide launcher. The device creates an electron cyclotron resonance (ECR) plasma in the launcher and a second ECR plasma is created in the line cusps due to a 0.0875 tesla magnetic field in that region. Additional special magnetic field configuring reduces the magnetic field at the substrate to below 0.001 tesla. The resulting plasma source is capable of producing large-area (20-cm diam), highly uniform (.+-.5%) ion beams with current densities above 5 mA/cm[sup 2]. The source has been used to etch photoresist on 5-inch diam silicon wafers with good uniformity. 3 figures.
Plasma generating apparatus for large area plasma processing
Tsai, Chin-Chi; Gorbatkin, Steven M.; Berry, Lee A.
A plasma generating apparatus for plasma processing applications is based on a permanent magnet line-cusp plasma confinement chamber coupled to a compact single-coil microwave waveguide launcher. The device creates an electron cyclotron resonance (ECR) plasma in the launcher and a second ECR plasma is created in the line cusps due to a 0.0875 tesla magnetic field in that region. Additional special magnetic field configuring reduces the magnetic field at the substrate to below 0.001 tesla. The resulting plasma source is capable of producing large-area (20-cm diam), highly uniform (.+-.5%) ion beams with current densities above 5 mA/cm.sup.2. The source has been used to etch photoresist on 5-inch diam silicon wafers with good uniformity.
The diverse applications of plasma
NASA Astrophysics Data System (ADS)
Sharma, Mukul; Dubey, Shivani; Darwhekar, Gajanan; Jain, Sudhir Kumar
Plasma being the fourth state of matter has always been an attraction for Physicists and Chemists. With the advent of time, plasma energy has been recognized in having widening horizons in the field of Biomedical Sciences. Plasma medicine can be subdivided into three main fields; Non-thermal atmospheric-pressure direct plasma for medical therapy; Plasma-assisted modification of bio-relevant surfaces and Plasma-based bio-decontamination and sterilization. The basis of the research is that as it has free carrier molecules, it has the ability to target specific cells and regulate functions like wound healing. Plasma does not harm healthy human cells but can kill bacteria and possibly even cancer cells to help treat various diseases. Nosocomial infection control, prevention and containment of contagious diseases, disinfection of medical devices, surface treatment (heat and UV sensitive surfaces) are research of interest. Recent success in generating plasma at very low temperature ie. Cold plasma makes the therapy painless. It has the ability to activate cellular responses and important mechanisms in the body. They target specific molecules such as prothrombin for blood coagulation, cytokines for killing bacteria, and angiogenesis for tissue regeneration. Plasma has bactericidal, fungicidal and virucidal properties. Plasma technology has flourishing future in diverse fields like Textiles, Nanofabrication, Automotives, Waste management, Microbiology, Food Hygiene, Medical Science like Skin treatments, sterilisation of wounds, Hand disinfection, Dental treatments etc. Food hygiene using plasma can be achieved in disinfection of food containers, food surface disinfection, hygiene in food handling, preparation and packaging. Therefore Plasma is most promising field for budding Scientist for fluorishing research in Biological Sciences.
The diverse applications of plasma
Sharma, Mukul Darwhekar, Gajanan; Dubey, Shivani; Jain, Sudhir Kumar
Plasma being the fourth state of matter has always been an attraction for Physicists and Chemists. With the advent of time, plasma energy has been recognized in having widening horizons in the field of Biomedical Sciences. Plasma medicine can be subdivided into three main fields; Non-thermal atmospheric-pressure direct plasma for medical therapy; Plasma-assisted modification of bio-relevant surfaces and Plasma-based bio-decontamination and sterilization. The basis of the research is that as it has free carrier molecules, it has the ability to target specific cells and regulate functions like wound healing. Plasma does not harm healthy human cells but can kill bacteria and possibly even cancer cells to help treat various diseases. Nosocomial infection control, prevention and containment of contagious diseases, disinfection of medical devices, surface treatment (heat and UV sensitive surfaces) are research of interest. Recent success in generating plasma at very low temperature ie. Cold plasma makes the therapy painless. It has the ability to activate cellular responses and important mechanisms in the body. They target specific molecules such as prothrombin for blood coagulation, cytokines for killing bacteria, and angiogenesis for tissue regeneration. Plasma has bactericidal, fungicidal and virucidal properties. Plasma technology has flourishing future in diverse fields like Textiles, Nanofabrication, Automotives, Waste management, Microbiology, Food Hygiene, Medical Science like Skin treatments, sterilisation of wounds, Hand disinfection, Dental treatments etc. Food hygiene using plasma can be achieved in disinfection of food containers, food surface disinfection, hygiene in food handling, preparation and packaging. Therefore Plasma is most promising field for budding Scientist for fluorishing research in Biological Sciences.
Rydberg atoms in ultracold plasmas
NASA Astrophysics Data System (ADS)
Rolston, Steven
Ultracold plasmas are formed through the photoionization of laser-cooled atoms, or spontaneous ionization of a dense cloud of Rydberg atoms or now molecules[1]. Ultracold plasmas are inherently metastable, as the ions and electrons would be in a lower energy state bound together as atoms. The dominant process of atom formation in these plasmas is three-body recombination, a collision between two electrons and an ion that leads to the formation of a Rydberg atom. This collisional process is not only important in determining the lifetime and density of the plasma, but is also critical in determining the time evolution of the temperature. The formation of the Rydberg atoms is accompanied by an increase in electron energy for the extra electron in the collision, and is a source of heating in these plasmas. Classical three-body recombination theory scales as T-9/2, and thus as a plasma cools due to a process such as adiabatic expansion, recombination-induced heating turns on, limiting the temperature [2]. The Rydberg atoms formed live in the plasma and contribute to the temperature dynamics, as collisions with plasma electrons can change the principal quantum number of the Rydberg atom, driving it to more tightly bound states (a source of plasma heating) or to higher states (a source of plasma cooling). If the plasma is cold and dense enough to be strongly coupled, classical three-body recombination theory breaks down. Recent theoretical work [3] suggests that the rate limits as the plasma gets strongly coupled. I will review the role of Rydberg atoms in ultracold plasmas and prospects for probing Rydberg collisions in the strongly coupled environment. [4pt] [1] J. P. Morrison, et al., Phys. Rev. Lett. 101, 205005 (2008 [0pt] [2] R. S. Fletcher, X. Zhang, and S. L. Rolston, Phys. Rev. Lett. 99, 145001 (2007 [0pt] [3] T. Pohl, private communication.
Hydrogen ionic plasma generated using Al plasma grid
NASA Astrophysics Data System (ADS)
Oohara, W.; Anegawa, N.; Egawa, M.; Kawata, K.; Kamikawa, T.
Negative hydrogen ions are produced in the apertures of a plasma grid made of aluminum under the irradiation of positive ions, generating an ionic plasma consisting of positive and negative ions. The saturation current ratio obtained using a Langmuir probe reflects the existence ratio of electrons and is found to increase in connection with the diffusion of the ionic plasma. The local increment of the current ratio suggests the collapse of negative ions and the replacement of detached electrons.
Electron density and plasma dynamics of a colliding plasma experiment
NASA Astrophysics Data System (ADS)
Wiechula, J.; Schönlein, A.; Iberler, M.; Hock, C.; Manegold, T.; Bohlender, B.; Jacoby, J.
We present experimental results of two head-on colliding plasma sheaths accelerated by pulsed-power-driven coaxial plasma accelerators. The measurements have been performed in a small vacuum chamber with a neutral-gas prefill of ArH2 at gas pressures between 17 Pa and 400 Pa and load voltages between 4 kV and 9 kV. As the plasma sheaths collide, the electron density is significantly increased. The electron density reaches maximum values of ≈8 ṡ 1015 cm-3 for a single accelerated plasma and a maximum value of ≈2.6 ṡ 1016 cm-3 for the plasma collision. Overall a raise of the plasma density by a factor of 1.3 to 3.8 has been achieved. A scaling behavior has been derived from the values of the electron density which shows a disproportionately high increase of the electron density of the collisional case for higher applied voltages in comparison to a single accelerated plasma. Sequences of the plasma collision have been taken, using a fast framing camera to study the plasma dynamics. These sequences indicate a maximum collision velocity of 34 km/s.
Enhancement of human plasma glucosylceramide assay sensitivity using delipidized plasma.
Zheng, Kefei; Ji, Allena; Chung, Lee Lee; Culm-Merdek, Kerry; Liu, Hanlan; Richards, Susan; Sung, Crystal
Glucosylceramide (GL-1) level in human has been considered as a surrogate biomarker for enzyme replacement and substrate reduction therapies (ERT and SRT) for Gaucher and Fabry patients. Due to the high endogenous level of GL-1 in human plasma, it is difficult to achieve the analytical sensitivity of plasma GL-1 below the normal endogenous level (1.7 μg/mL to 6.6 μg/mL) when using the standard addition method and regular plasma matrix for standard curve. A high sensitivity plasma GL-1 assay with LLOQ at 0.1 μg/mL was developed and validated using delipidized plasma so that patient plasma concentrations that are below normal reference range can be measured accurately. The normal reference range was established from 120 healthy donors using this developed new method. Twenty-three Fabry patient plasma samples including baseline and post-investigation drug treatment samples were measured. All post-treatment samples showed GL-1 concentration below 2.0 μg/mL, indicating the utility of the reported high sensitivity assay using delipidized plasma for monitoring the plasma GL-1 biomarker level in patients. PMID:27547732
A contoured gap coaxial plasma gun with injected plasma armature
NASA Astrophysics Data System (ADS)
Witherspoon, F. Douglas; Case, Andrew; Messer, Sarah J.; Bomgardner, Richard; Phillips, Michael W.; Brockington, Samuel; Elton, Raymond
A new coaxial plasma gun is described. The long term objective is to accelerate 100-200 μg of plasma with density above 1017 cm-3 to greater than 200 km/s with a Mach number above 10. Such high velocity dense plasma jets have a number of potential fusion applications, including plasma refueling, magnetized target fusion, injection of angular momentum into centrifugally confined mirrors, high energy density plasmas, and others. The approach uses symmetric injection of high density plasma into a coaxial electromagnetic accelerator having an annular gap geometry tailored to prevent formation of the blow-by instability. The injected plasma is generated by numerous (currently 32) radially oriented capillary discharges arranged uniformly around the circumference of the angled annular injection region of the accelerator. Magnetohydrodynamic modeling identified electrode profiles that can achieve the desired plasma jet parameters. The experimental hardware is described along with initial experimental results in which approximately 200 μg has been accelerated to 100 km/s in a half-scale prototype gun. Initial observations of 64 merging injector jets in a planar cylindrical testing array are presented. Density and velocity are presently limited by available peak current and injection sources. Steps to increase both the drive current and the injected plasma mass are described for next generation experiments.
Momentum transfer to rotating magnetized plasma from gun plasma injection
NASA Astrophysics Data System (ADS)
Hassam, A. B.; Shamim, Imran; Ellis, R. F.; Witherspoon, F. D.; Phillips, M. W.
Numerical simulations are carried out to investigate the penetration and momentum coupling of a gun-injected plasma slug into a rotating magnetized plasma. An experiment along these lines is envisioned for the Maryland Centrifugal Experiment (MCX) using a coaxial plasma accelerator gun developed by HyperV Technologies Corp. The plasma gun would be located in the axial mid-plane and fired off-axis into the rotating MCX plasma annulus. The numerical simulation is set up so that the initial momentum in the injected plasma slug is of order the initial momentum of the target plasma. Several numerical firings are done into cylindrical rotating plasma. Axial symmetry is assumed. The slug is seen to penetrate readily and deform into a mushroom, characteristic of interchange deformations. It is found that upto 25% of the momentum in the slug can be transferred to the background plasma in one pass across a cylindrical chord. For the same initial momentum, a high-speed low density slug gives more momentum transfer than a low-speed high density slug. Details of the numerical simulations and a scaling study are presented.
A contoured gap coaxial plasma gun with injected plasma armature.
Witherspoon, F Douglas; Case, Andrew; Messer, Sarah J; Bomgardner, Richard; Phillips, Michael W; Brockington, Samuel; Elton, Raymond
A new coaxial plasma gun is described. The long term objective is to accelerate 100-200 microg of plasma with density above 10(17) cm(-3) to greater than 200 km/s with a Mach number above 10. Such high velocity dense plasma jets have a number of potential fusion applications, including plasma refueling, magnetized target fusion, injection of angular momentum into centrifugally confined mirrors, high energy density plasmas, and others. The approach uses symmetric injection of high density plasma into a coaxial electromagnetic accelerator having an annular gap geometry tailored to prevent formation of the blow-by instability. The injected plasma is generated by numerous (currently 32) radially oriented capillary discharges arranged uniformly around the circumference of the angled annular injection region of the accelerator. Magnetohydrodynamic modeling identified electrode profiles that can achieve the desired plasma jet parameters. The experimental hardware is described along with initial experimental results in which approximately 200 microg has been accelerated to 100 km/s in a half-scale prototype gun. Initial observations of 64 merging injector jets in a planar cylindrical testing array are presented. Density and velocity are presently limited by available peak current and injection sources. Steps to increase both the drive current and the injected plasma mass are described for next generation experiments. PMID:19725654
MHD description of plasma: handbook of plasma physics
Kulsrud, R.M.
The basic sets of MHD equations for the description of a plasma in various limits are derived and their usefulness and limits of validity are discussed. These limits are: the one fluid collisional plasma, the two fluid collisional plasma, the Chew-Goldberger Low formulation of the guiding center limit of a collisionless plasma and the double-adiabatic limit. Conservation relations are derived from these sets and the mathematics of the concept of flux freezing is given. An example is given illustrating the differences between guiding center theory and double adiabatic theory.
Surface plasma wave excitation via laser irradiated overdense plasma foil
Kumar, Pawan; Tripathi, V. K.
A laser irradiated overdense plasma foil is seen to be susceptible to parametric excitation of surface plasma wave (SPW) and ion acoustic wave (IAW) on the ion plasma period time scale. The SPW is localised near the front surface of the foil while IAW extends upto the rear. The evanescent laser field and the SPW exert a ponderomotive force on electrons driving the IAW. The density perturbation associated with the latter beats with the laser induced oscillatory electron velocity to drive the SPW. At relativistic laser intensity, the growth rate is of the order of ion plasma frequency.
Revisiting the plasma sheath—dust in plasma sheath
NASA Astrophysics Data System (ADS)
Das, G. C.; Deka, R.; Bora, M. P.
In this work, we have considered the formation of warm plasma sheath in the vicinity of a wall in a plasma with considerable presence of dust particles. As an example, we have used the parameters relevant in case of plasma sheath formed around surfaces of various solid bodies in space, though the results obtained in this work can be applied to any other physical situation such as laboratory plasma. In the ion-acoustic time scale, we neglect the dust dynamics. The dust particles affect the sheath dynamics by affecting the Poisson equation which determines the plasma potential in the sheath region. It is important to note that our calculations are valid only when the amount of dust particles is not sufficient so as to affect the plasma dynamics in the dust-acoustic time scale, but enough to affect the plasma sheath. We have assumed the current to a dust particle to be balanced throughout the analysis. This makes the grain potential dependent on plasma potential, which is then incorporated into the Poisson equation. The resultant numerical model becomes an initial value problem, which is described by a 1-D integro-differential equation, which is then solved self-consistently by incorporating the change in plasma potential caused by inclusion of the dust potential in the Poisson equation.
Plasma Sterilization Technology for Spacecraft Applications
NASA Technical Reports Server (NTRS)
Fraser, S. J.; Olson, R. L.; Leavens, W. M.
The application of plasma gas technology to sterilization and decontamination of spacecraft components is considered. Areas investigated include: effective sterilizing ranges of four separate gases; lethal constituents of a plasma environment; effectiveness of plasma against a diverse group of microorganisms; penetrating efficiency of plasmas for sterilization; and compatibility of spacecraft materials with plasma environments. Results demonstrated that plasma gas, specifically helium plasma, is a highly effective sterilant and is compatible with spacecraft materials.
Surface currents on ideal plasmas
Webster, Anthony J.
The surface (or 'skin') current that can flow at a perturbed interface between plasma and vacuum is considered in the approximation where a surface marks a sharp transition from plasma to vacuum. A short magnetohydrodynamic calculation gives an exact and general expression for the component perpendicular to the average of the magnetic field either side of the surface, finding it proportional to the edge plasma pressure. A consequence is that for all plasmas with zero surface current at equilibrium, the surface current associated with any linear instability will flow parallel to the magnetic field. The surface current is calculated for a simple but realistic model of a cylindrical plasma, and found to depend on the type of instability, and consequently on the particular plasma equilibrium. This is illustrated for two well known cases.
Variable frequency microwave excited plasma
Gathi, Z.; Wei, J.; Garard, S.; Lauf, R.J.; Clausing, R.; McMillan, A.
This paper reports on the use of an agile frequency source in generating plasma. A Traveling Wave Tube (TWT) provides approximately one octave bandwidth and variable power level up to 2 KW. By controlling the frequency, efficient coupling to the load (materials and/or plasma) can be maintained even as the load is changing in properties or position. Furthermore, the variable frequency power source allows the localization of the plasma discharge in precise areas of interest to specific processes. The excitation frequencies can be continuously swept to scan the plasma across an arbitrary-shaped target surface. Plasma generation and position control is reviewed and experimental results on variable frequency microwave excited plasma are presented.
NASA Astrophysics Data System (ADS)
Brown, Michael R.; Schaffner, David A.
A new turbulent plasma source at the Swarthmore Spheromak Experiment (SSX) facility is described. The MHD wind tunnel configuration employs a magnetized plasma gun to inject high-beta plasma into a large, well-instrumented, vacuum drift region. This provides unique laboratory conditions approaching that in the solar wind: there is no applied background magnetic field in the drift region and has no net axial magnetic flux; the plasma flow speed is on the order of the local sound speed (M ~ 1), so flow energy density is comparable to thermal energy density; and the ratio of thermal to magnetic pressure is of order unity (plasma β ~ 1) so thermal energy density is also comparable to magnetic energy density. Results presented here and referenced within demonstrate the new capabilities and show how the new platform is proving useful for fundamental plasma turbulence studies.
NASA Astrophysics Data System (ADS)
Giannelli, Sebastiano; Andreussi, Tommaso; Pegoraro, Francesco; Andrenucci, Mariano
A fundamental description of the plasma acceleration process in magnetoplasmadynamic (MPD) thrusters is presented. The properties of plasma flows in self-field MPD thrusters are investigated by adopting a stationary, axisymmetric, resistive magnetohydrodynamic plasma model. First, the acceleration process in a cylindrical MPD channel is analyzed by neglecting the gasdynamic pressure term. A class of solutions is presented, which allows for a simple analytical treatment of the flow. The physical and mathematical nature of the flow is thus described in terms of two characteristic parameters: a dimensionless channel length, scaled with the plasma resistive length, and a dimensionless parameter which depends on the applied voltage. Then, the effect of gasdynamic pressure is investigated. The presented approach gives an effective description of the plasma acceleration process and defines a framework for the parametric analysis of plasma flows in MPD thrusters. Alta SpA: www.alta-space.com.
Electron cyclotron resonance plasma photos
Racz, R.; Palinkas, J.; Biri, S.
In order to observe and study systematically the plasma of electron cyclotron resonance (ECR) ion sources (ECRIS) we made a high number of high-resolution visible light plasma photos and movies in the ATOMKI ECRIS Laboratory. This required building the ECR ion source into an open ECR plasma device, temporarily. An 8MP digital camera was used to record photos of plasmas made from Ne, Ar, and Kr gases and from their mixtures. We studied and recorded the effect of ion source setting parameters (gas pressure, gas composition, magnetic field, and microwave power) to the shape, color, and structure of the plasma. The analysis of the photo series gave us many qualitative and numerous valuable physical information on the nature of ECR plasmas.
Slotted antenna waveguide plasma source
NASA Technical Reports Server (NTRS)
Foster, John (Inventor)
A high density plasma generated by microwave injection using a windowless electrodeless rectangular slotted antenna waveguide plasma source has been demonstrated. Plasma probe measurements indicate that the source could be applicable for low power ion thruster applications, ion implantation, and related applications. This slotted antenna plasma source invention operates on the principle of electron cyclotron resonance (ECR). It employs no window and it is completely electrodeless and therefore its operation lifetime is long, being limited only by either the microwave generator itself or charged particle extraction grids if used. The high density plasma source can also be used to extract an electron beam that can be used as a plasma cathode neutralizer for ion source beam neutralization applications.
Plasma ignition for laser propulsion
NASA Technical Reports Server (NTRS)
Askew, R. F.
For a specific optical system a pulsed carbon dioxide laser having an energy output of up to 15 joules was used to initiate a plasma in air at one atmosphere pressure. The spatial and temporal development of the plasma were measured using a multiframe image converter camera. In addition the time dependent velocity of the laser supported plasma front which moves opposite to the direction of the laser pulse was measured in order to characterize the type of wavefront developed. Reliable and reproducible spark initiation was achieved. The lifetime of the highly dense plasma at the initial focal spot was determined to be less than 100 nanoseconds. The plasma front propagates toward the laser at a variable speed ranging from zero to 1.6 x 1,000,000 m/sec. The plasma front propagates for a total distance of approximately five centimeters for the energy and laser pulse shape employed.
Plasma Sail Concept Fundamentals
NASA Technical Reports Server (NTRS)
Khazanov, G. V.; Delamere, P.; Kabin, K.; Linde, T. J.
The mini-magnetospheric plasma propulsion (M2P2) device, originally proposed by Winglee et al., predicts that a 15-km standoff distance (or 20-km cross-sectional dimension) of the magnetic bubble will provide for sufficient momentum transfer from the solar wind to accelerate a spacecraft to unprecedented speeds of 50 C80 km/s after an acceleration period of 3 mo. Such velocities will enable travel out of the solar system in period of 7 yr almost an order of magnitude improvement over present chemical-based propulsion systems. However, for the parameters of the simulation of Winglee et al., a fluid model for the interaction of M2P2 with the solar wind is not valid. It is assumed in the magnetohydrodynamic (MHD) fluid model, normally applied to planetary magnetospheres, that the characteristic scale size is much greater than the Larmor radius and ion skin depth of the solar wind. In the case of M2P2, the size of the magnetic bubble is actually less than or comparable to the scale of these characteristic parameters. Therefore, a kinetic approach, which addresses the small-scale physical mechanisms, must be used. A two-component approach to determining a preliminary estimate of the momentum transfer to the plasma sail has been adopted. The first component is a self-consistent MHD simulation of the small-scale expansion phase of the magnetic bubble. The fluid treatment is valid to roughly 5 km from the source and the steady-state MHD solution at the 5 km boundary was then used as initial conditions for the hybrid simulation. The hybrid simulations showed that the forces delivered to the innermost regions of the plasma sail are considerably ( 10 times) smaller than the MHD counterpart, are dominated by the magnetic field pressure gradient, and are directed primarily in the transverse direction.