text:
Volume 529, May 2011
|Article Number
|Number of page(s)
|The Sun
|Published online
|04 April 2011
Characteristics of the flare acceleration region derived from simultaneous hard X-ray and radio observations
1 Department of Physics and Astronomy, University of Glasgow, G12 8QQ, UK
2 LESIA, Observatoire de Paris, CNRS, UPMC, Université Paris-Diderot, 5 place Jules Janssen, 92195 Meudon Cedex, France
e-mail: email@example.com
Received: 22 November 2010
Accepted: 8 February 2011
We investigate the type III radio bursts and X-ray signatures of accelerated electrons in a well-observed solar flare in order to find the spatial properties of the acceleration region. Combining simultaneous RHESSI hard X-ray flare data and radio data from Phoenix-2 and the Nançay radioheliograph, the outward transport of flare accelerated electrons is analysed. The observations show that the starting frequencies of type III bursts are anti-correlated with the HXR spectral index of solar flare accelerated electrons. We demonstrate both analytically and numerically that the type III burst starting location is dependent upon the accelerated electron spectral index and the spatial acceleration region size, but weakly dependent on the density of energetic electrons for relatively intense electron beams. Using this relationship and the observed anti-correlation, we estimate the height and vertical extent of the acceleration region, giving values of around 50 Mm and 10 Mm, respectively. The inferred acceleration height and size suggest that electrons are accelerated well above the soft X-ray loop-top, which could be consistent with the electron acceleration between 40 Mm and 60 Mm above the flaring loop.
Key words: Sun: flares / Sun: radio radiation / Sun: X-rays, gamma rays / Sun: particle emission
1. Introduction
Accelerated electron beams are believed to be responsible for both hard X-ray (HXR) and coherent radio emission during solar flares. Upwardly travelling electron beams propagate through the coronal plasma and sometimes escape into interplanetary space. Emission from such beams is often observed as coronal and interplanetary type III radio bursts. Electron beams travelling downwards with small pitch angles enter the dense plasma of the chromosphere and are generally seen through bremsstrahlung emission in HXR. Before entering the chromosphere, downwardly propagating electron beams may also produce reverse type III bursts. Despite this wealth of electromagnetic beam emission from accelerated electrons propagating in plasma, the location of the electron acceleration site and its spatial characteristics are poorly known.
Indirect evidence of electron acceleration sites first came from broad band radio spectral observations of pairs of type III and reverse type III bursts (e.g. Aschwanden et al. 1995a; Aschwanden & Benz 1997). The starting frequencies of these burst pairs are found between 220 − 910 MHz, implying a range of electron densities in the acceleration region between 6 × 108 − 1010 cm-3 for fundamental emission or 1.5 × 108 − 3 × 109 cm-3 for harmonic emission. These densities are lower than ones observed in bright soft X-ray loops (2 × 1010 − 2 × 1011 cm-3) suggesting that the acceleration region lies above the soft X-ray loops, being located for example in a cusp reconnection site. HXR observations have also been independently used to provide insight into typical electron acceleration region heights above the photosphere. Through electron time-of-flight analysis using HXR emission in the range 20 − 200 keV (Aschwanden et al. 1998), height estimates have been found in the range 20 − 50 Mm. The spatial size of the acceleration region still remains largely unknown.
The simultaneous observation of HXR and metric/decimetric radio emission is commonplace during flares and the relationship between type III bursts and hard X-ray emissions has been studied for many years (see for example Pick & Vilmer 2008, for a review). The first studies performed by Kane (1972) found a good similarity between HXR and type III radio emission, suggesting the two emissions are produced by electrons originating from a common acceleration site. Many subsequent studies have specifically dealt with the association of coherent type III radio emission and HXR bursts, both statistically (e.g. Kane 1972, 1981; Hamilton et al. 1990; Aschwanden et al. 1995a; Arzner & Benz 2005) and for individual events (e.g. Kane et al. 1982; Benz et al. 1983; Dennis et al. 1984; Raoult et al. 1985; Aschwanden et al. 1995b; Raulin et al. 2000; Vilmer et al. 2002). A more recent statistical study of 201 flares above GOES class C5 (Benz et al. 2005) reports an 83% association rate with coherent radio emission, within the range between 4 GHz and 100 MHz. These results suggest that practically all flares with HXR GOES class > C5 are associated with some form of coherent radio emission.
An in depth statistical study was carried out between radio type III bursts and HXRs by (Kane 1981). The study reported that the X-ray/type III correlation increases systematically with the intensity of HXR and radio emission, the peak spectral hardness of HXR emission and the type III burst starting frequency. Hamilton et al. (1990) similarly reported the systematic increase of HXR/type III correlation with increasing emission intensity and to a lesser extent with spectral index of HXR emission. Hamilton et al. (1990) also reported a statistical correlation between the peak HXR and type III intensities. To produce a harder (smaller spectral index) HXR photon spectrum requires a harder electron beam spectrum. A hard electron beam spectrum is an attractive attribute for type III producing electron beams as it makes it easier and faster for the bump-in-tail instability to occur. Faster instability onset ties in very well with the HXR/type III correlation increasing for bursts with a higher starting frequency.
A temporal correlation between HXR and radio pulses has been found statistically (Aschwanden et al. 1995a) where the average time delay betwen the HXR pulse and radio pulse starting frequency was ≤ 0.1 s. Temporal correlations have also been found in many individual event studies. Of these studies the results by Dennis et al. (1984) find a temporal correlation with a similar magnitude to the statistical study by Aschwanden et al. (1995a). This, together with previous correlations, suggests a common acceleration region with HXR producing electron beams having either slightly less distance to travel or slightly more energetic electrons responsible for the emission. The simultaneous analysis of HXR and type III radio bursts is thus an attractive diagnostic of flare associated electron acceleration.
A few previous studies have attempted to infer properties (both height and size) of the common electron acceleration region from simultaneous HXR and radio observations. Kane et al. (1982) used an inferred spectral index from HXR emission to estimate the minimum distance required for the type III producing electron beam to become unstable. With an assumed electron acceleration height of 20 Mm, an altitude of 100 Mm was deduced for the starting frequency, in good agreement with the spectral observations. Unfortunately the type III frequencies in this analysis were too high with respect to the Nançay radioheliograph frequencies for radio imaging at this time so it was not possible to confirm the starting height of the radio emission. Benz et al. (1983) also considered the minimum distance required for a type III producing electron beam to become unstable. By modelling both the HXR and radio producing electron beam as a Maxwellian they found a weak correlation between the type III starting frequency and the electron temperature derived from HXR observations above 26 keV. However, in the event considered a change in electron temperature cannot fully account for the initial change in type III starting frequency. The authors thus conclude that a movement of the acceleration site occurred for this event.
In another study Aschwanden et al. (1995a) uses the assumption of a common acceleration region producing upward and downward electron beams to estimate acceleration times and infer acceleration region sizes. No frequency gap was observed between type III and reverse type III emission so their starting frequency separation distance was constrained by the detector resolution. Using an assumed density model, this distance was found to be < 2 Mm. The instability distance for the electron beam was then equated to twice this resolution. By using a similar analysis of Kane et al. (1982) with observed HXR spectral index, acceleration times are found with Δt < 0.3−3 ms. The size of the acceleration region is then inferred at 0.7 Mm. This constraint of acceleration site size and times is heavily dependent upon the assumption of bidirectional electron beams starting with a separation unresolved by the detector and thus should be treated with care.
Non-thermal HXR emission detected above 20 keV provides information on the overall spectrum of accelerated electrons, usually represented by a power-law in velocity and/or energy space. It also provides insight on the density of the non-thermal electrons required to explain the HXR emission. Radio type III bursts are believed to be formed via coherent plasma emission mechanisms requiring the presence of Langmuir wave turbulence (Ginzburg & Zhelezniakov 1958). The high level of Langmuir waves infers a local electron beam-plasma instability. Assuming that some acceleration mechanism in the corona produces a power-law in energy space the required unstable distribution can be formed due to electron transport parallel to the magnetic field. Therefore, the criteria for beam instability and hence starting frequency of the type III emission are linked to the properties of the acceleration region; the spatial size, the spectral index of energised electrons, and the height in the corona.
In some events upward electron beams are able to travel from the corona to the inner heliosphere and create interplanetary type III bursts. Previous work (Kontar & Reid 2009; Reid & Kontar 2010) has modelled electron beam transport from the Sun to the Earth taking into account the self-consistent generation of Langmuir waves. Kontar & Reid (2009) found that wave-particle interactions are required to explain both electron beam onset times and spectral properties at 1 AU. Developing this model further, Reid & Kontar (2010) found the inclusion of density turbulence suppressed the growth of Langmuir waves which led to a broken power-law spectra similar to observational results (Krucker et al. 2009).
Electron beams escaping into the inner heliosphere can also be detected in-situ near 1 AU and their numbers have been correlated to the number of HXR producing electrons (Krucker et al. 2007). A correlation is found between the spectral indices of both electron populations as well as between the numbers of HXR producing electrons and escaping electrons for prompt electron events. This again suggests that the X-ray producing electrons and the electrons moving upward in the corona originate from a common acceleration site. Furthermore, it is found that the number of escaping electrons is on average only of the HXR-producing electrons above 50 keV.
In this paper we show that simultaneous radio and X-ray observations can be used with a simple analytical model to diagnose not only the location but the size of the acceleration region as well as the location. This provides one of the first observational estimates of acceleration region size. The present analysis of the April 15th 2002 at 08:51 UT suggests the acceleration region is located at heights of ≈ 50 Mm and has a spatial size of ≈ 10 Mm. Numerical simulations are used with these inputs to help validate the results and explore unknown electron beam parameters.
2. Basic concepts: starting frequency of type III bursts
The aim of the following theory is to relate known observational variables from flares to unknown flare parameters. Specifically we will relate the starting frequency of type III bursts and the spectral index of the inducing electron beam to the height and size of a flare acceleration region. Initially let us consider the propagation of a flare accelerated electron cloud with starting characteristic size d located at an initial height r = 0. The initial distribution is given by (1)where g0(v) is the initial electron velocity distribution. Langmuir waves will be generated when the quasilinear growth rate γ(v,r) of electrons resonantly interacting (ωpe(r) = kv) with Langmuir waves (Drummond & Pines 1962; Vedenov et al. 1962) becomes stronger than the collisional absorption γc by the Maxwellian plasma (2)where lnΛ is the Coulomb logarithm, taken near 20 for the parameters in the corona. ωpe(r), ne(r) and vTe are the background plasma frequency, density and thermal velocity respectively.
The initial velocity distribution of solar flare accelerated particles is usually taken as a power-law g0(v) ~ v − α. This distribution at t = 0 is stable and will not lead to generation of Langmuir waves. At later times t > 0 the propagation of particles leads to the formation of a positive slope of the distribution function in velocity space. The distribution function changes in time due to the propagation (in the case of no energy losses) (3)and the growth rate for Langmuir waves becomes (4)We can observe strong Langmuir wave growth remotely via observations of type III radio emission. Langmuir wave growth should occur at the distance Δr = htype III − hacc from the original location where htype III is a height corresponding to the starting frequency of type III bursts and hacc is the acceleration region height. The distance Δr can be found by equating the growth rate for Langmuir waves given in Eq. (4) with γc giving (5)The quantity vg0(v) = nb where nb is the inducing electron beam density. By assuming a coronal background electron density of 109 cm-3, a coronal electron temperature of 2 MK and a beam density of 104 cm-3 the second term γcne(r)/πωpe(r)nb is around 10-3 ≪ α. Thus the relation between the acceleration site properties and the type III starting frequency is determined mostly by the spectral slope of the electron beam giving the simple relation (6)The unknown parameters hacc and d can be found from the known parameters α and htype III. A key advantage of this relation lies with its lack of dependence on the poorly known electron beam number density necessary to produce type III emission. The method is similar to what was discussed in Kane et al. (1982). The key difference is that we consider an instantaneous injection at t = 0 with a spatially broad distribution function while Kane et al. (1982) considers a temporal injection from a point source.
Fig. 1
The morphology of the April 15, 2002 solar flare. Background is SOHO/EIT 195 image. The small red contour lines at the base of the plasma loops on the left correspond to HXR photons imaged by RHESSI in the 15 − 30 keV range. The large contours on the right hand side correspond to NRH radio images at frequencies 432 MHz (blue), 327 MHz (orange), 236 MHz (pink), 164 MHz (yellow).
3. Observations and data analysis
3.1. Instruments
In this study, RHESSI (Lin et al. 2002) data is used to analyse the HXR emission from downward propagating electron beams. By assuming a common acceleration site for upward and downward electron beams, the X-ray emission observed by RHESSI can serve to provide the spectral index for the above prediction. RHESSI can also provide spatial information regarding the HXR.
When observing the radio emission in the corona, the spectral information was obtained by using Phoenix-2 radiospectrometer (Messmer et al. 1999) within the frequency range 100 − 700 MHz. This provides information we use to find the starting frequency of the type III radio emission. The spatial information for type III radio emission was found by using the Nançay radioheliograph (NRH) (Kerdraon & Delouis 1997) in the frequency range of 164 − 432 MHz. The spatial radio information observed by the NRH can make sure the observed radio flux is emitted from the same active region in the solar atmosphere responsible for the HXR emission.
3.2. Selection
We aimed our study at cases observed simultaneously with the NRH, Phoenix-2 and RHESSI. We started our selection from a list of events presented in previous observational analysis between coherent radio and HXR emissions (Arzner & Benz 2005; Grigis & Benz 2004; Benz et al. 2005). Of the 58 events considered, 10 were found to have coherent radio emission in the frequencies covered by the NRH observations. We selected one event which had a simple spatial configuration at all NRH radio wavelengths, clearly defined starting frequencies and a strong HXR flux. This event was chosen as an illustration of the method.
3.3. Measurements
The spatial overview of the April 15th flare is presented in Fig. 1 using RHESSI, NRH and SOHO/EIT. The X-ray source was imaged using RHESSI in the energy range between 15 and 30 keV. The higher energies had too few photons to make a reasonable image above the background noise. The radio source was imaged using the NRH in frequency bands from 164 to 432 MHz and the size increases with decreasing frequency. This can provide an estimate regarding the radial magnetic field expansion locally in the corona. However, the decrease of spatial resolution with decreasing frequency using the NRH has to be considered. This decrease behaves as D/λ where D is the maximum antenna spatial separation and λ is the wavelength of the radio emission. The SOHO/EIT 195 image displays information about the overlying plasma configuration, conferring insight into the magnetic field structure where the flare originates. The temporal evolution of the flare is presented in Fig. 2, using Phoenix-2, NRH and RHESSI data.
Fig. 2
Time evolution of the radio and HXR fluxes for the April 15, 2002 solar flare between 08:51 and 08:54 UT. The top panel is the Phoenix-2 radiospectrometer data on a log scale between the frequencies 160 and 700 MHz. The middle panel is the Nançay radioheliograph flux time profiles observed at 5 discrete frequencies from 164 to 432 MHz. The bottom panels are the RHESSI HXR counts/second at the three energy ranges 6−12, 12−25 and 25−50 keV.
The spectral index of the X-ray emission, γ, was obtained using RHESSI spectral analysis of the photon flux I(ϵ) ~ ϵ − γ. The photon spectral index γ was estimated using a power-law fit every 2 s (half-rotation of the spacecraft). The one sigma error associated with the power-law fit was used as the spectral index error estimates.
The starting frequency of the type III radio emission was determined from the Phoenix-2 data. We used Phoenix-2 data with a 1 s temporal resolution. The mean value of the radio flux on the quiet 3 min interval 08:56 UT to 08:59 UT was used to quantify the background level for each frequency channel. A threshold of twice this background level was then used at every moment in time to determine the starting frequency of the radio emission. We then averaged the starting frequency over the 2 s RHESSI interval. The mean width of the radio channels between 100 and 700 MHz was 9.2 MHz so we took 10 MHz as the one sigma error on the starting frequency.
The combined determination of starting frequencies and spectral indices was done on two time periods between 08:51:20 → 08:51:36 UT and 08:52:38 → 08:53:00 UT. Both periods have a HXR non-thermal spectral index below 7.5 at all points in time. Moreover, throughout both periods there is significant radio emission above the threshold frequency.
The temporal evolution of γ and the type III starting frequency is overplotted on the Phoenix-2 data in Fig. 3 for the time periods defined above. The photon spectral index displays an anti-correlation with the type III starting frequency. A clearer visualisation of this anti-correlation can be seen when both observables are plotted against each other (Fig. 4). They have a Pearson correlation coefficient of –0.65 due to the starting frequency decreasing as the spectral index increases. This correlation suggests that the two variables are related by a linear fit.
Fig. 3
HXR spectral index and frequency spectra of the type III burst for two different time periods in the April 15, 2002 event. The starting frequencies are plotted as red stars connected by dashed lines. The HXR spectral indices are plotted as 2 s green bars with error bars in the middle of their integration time.
Fig. 4
Scatter plot of the HXR photon spectral index vs. the starting frequencies of the type III burst. The one sigma observational errors on both spectral index and starting frequency are shown.
3.4. Acceleration region
To infer the characteristics of the coronal acceleration region from Eq. (6) we must use some assumptions to obtain htype III and α from the type III starting frequency and γ. To relate the starting height of the type III emission htype III to the starting frequency we have used the exponential density model derived in Paesold et al. (2001) which assumes second harmonic emission for a reference height of around 1.5 Rs for 160 MHz emission. To obtain the electron beam spectral index in velocity space from the photon spectral index in energy space, the thick target model (Brown 1971; Brown et al. 2006) was assumed. The electron beam spectral index α can then be calculated from the photon spectral index γ through the simple relationship α = 2(γ + 1). The effect of photosphere albedo is ignored as the flare is located close to the limb (Kontar & Jeffrey 2010).
A positive correlation between the electron beam velocity spectral index and the starting height is observed with a Pearson correlation coefficient of 0.62 (Fig. 5). To investigate the correlation and obtain estimates of the acceleration region properties a linear fit was applied to the data. The routine mpfitexy (Markwardt 2009) was used to obtain a fit to the data including observational error (Fig. 5). Using Eq. (6) the linear fit infers the acceleration region height and size values of hacc = 52 ± 21 Mm and d = 10.5 ± 1.6 Mm respectively. The larger percentage error of the height in relation to the size can be observed in the extremes of the fit shown in Fig. 5. If this linear relationship is statistically significant the slope has to be greater than zero. We can test the null hypothesis that the slope is zero using the Students t-statistic (e.g. Press et al. 1992). A t-score of 6.56 is found with 19 degrees of freedom. Using a confidence level of 0.01 we can comfortably reject the null hypothesis and say the linear relation is statistically significant.
Fig. 5
Scatter plot of electron beam spectral index in velocity space, α, calculated from the HXR photon spectral index vs. the distance above the photosphere associated with the starting frequencies of the type III burst. The one sigma observational errors on both spectral index and height are shown. The green dashed line is a linear fit to the data including observational error with the green dotted lines showing the extremes of the fit.
The radio threshold frequency used to constrain the starting frequencies had a minor effect on the results if changed within reasonable parameters. Different levels (1.5−2.5 × background level) changed the acceleration region properties by around 5−10%. Higher threshold frequencies caused higher hacc and lower d with the converse being true. Threshold frequencies <1.5 or >2.5 × background level caused unrealistic acceleration region parameters as starting frequencies were either not detected or were detected at high frequencies not corresponding to the visually observed type III emission.
4. Numerical simulations of Langmuir wave generation
To explore these predictions for acceleration height and size we can use numerical simulations of electron beams and induced Langmuir waves in the solar corona. The simulations allow us to validate the observational result given the known initial conditions and check the validity of Eq. (6). Moreover, it allows us to explore some of the unknown parameters such as beam density and the level of Langmuir waves required for radio emission.
4.1. Electron beam transport
The evolution of accelerated electrons can be considered self-consistently using weak turbulence theory where we have also taken into account binary collisions of energetic electrons with the surrounding plasma. We consider the time evolution of an electron distribution function f(v,r,t) and the induced Langmuir wave spectral energy density W(v,r,t). The energetic electrons travel in a beam-like structure along the magnetic field which radially expands outwards into the corona, allowing a one dimensional treatment of their propagation via The background plasma is assumed to be a Maxwellian distribution with thermal velocity vTe, density ne(r) and plasma frequency ωpe(r). The background plasma damps through collisions both the electron beam (last term of Eq. (7)) and the Langmuir waves () (e.g. Melrose 1980). Coulomb collisions also spontaneously induce Langmuir waves (last term of Eq. (8)) (e.g. Hannah et al. 2009). The first terms on the right hand side of Eqs. (7,8) describe the resonant interaction ωpe(r) = kv of electrons and Langmuir waves (Drummond & Pines 1962; Vedenov et al. 1962). This resonant interaction is also responsible for Landau damping of Langmuir waves with phase velocities near vTe, described through (Lifshitz & Pitaevskii 1981).
As the density of the background plasma changes with distance from the Sun, Langmuir waves experience wave refraction. This effect is described through the third term in Eq. (8) where the level of background plasma inhomogeneity is characterised through l-1 = ωpe(r)-1∂ωpe(r)/∂r (e.g. Ryutov 1969; Kontar 2001).
The spatial propagation of electron beam and Langmuir waves are described by the second term in Eqs. (7,8). Electron beam spatial propagation also includes the magnetic field expansion within the corona (Reid & Kontar 2010). This expansion in the corona is modelled through an expanding cone which has an angle θ and starts at length r0 from the acceleration region. The coronal expansion conserves the total number of electrons such that for scatter-free propagation, ∫(r + r0)2ne(r)dr = const. along the magnetic field lines.
4.2. Initial conditions
The system of equations is solved numerically for an initially localised electron beam (9)The initial distribution is characterised by d the acceleration region size, vmin the minimum electron velocity considered, α the beam spectral index, and nb the density of the electron beam above vmin. The background plasma absorbs Langmuir waves with phase velocity close to the thermal velocity via Landau damping therefore we set vmin to 8vTe and safely ignore velocities lower than vmin.
The thermal spectral energy density of Langmuir waves (e.g. Hannah et al. 2009) is the initial condition given by (10)where Te is the background plasma temperature set at 2 MK and kB is Boltzmann constant. This is the expression for the thermal level of a Maxwellian plasma when collisions are weak.
The background density ne(r) was defined using the same exponential density model (Paesold et al. 2001) that was assumed in the previous section.
4.2.1. Observational constraints
The values derived from the observations in the previous section constrain some of the key input parameters for the simulations. The starting height, hacc = 52 Mm which corresponds to a background density of ne = 3 × 109 cm-3 using the exponential density model given in Paesold et al. (2001). This gives a plasma frequency of 500 MHz relating to second harmonic emission of 1000 MHz. The characteristic beam size d = 10.5 Mm. The HXR spectral index γ is found from the RHESSI observations (Fig. 5) which allows us to constrain the electron velocity spectral index as 6 ≤ α ≤ 16.
The NRH images of the type III radio emission allow us to observe how the radio source increases with decreasing frequency. Such an observation can provide information regarding the magnetic field expansion. The size of the radio emission at 237 MHz is approximately twice the size of the radio emission at 432 MHz taken at 30% of emission level. This was measured around the two peak times of emission at 08:51:21 UT and 08:52:42 UT. However, the wavelength λ is approximately twice as large at 237 MHz compared to 432 MHz and so the angular resolution of the NRH is increased by two. Moreover, scattering by density inhomogeneities will increases the apparent size of the coronal radio source more at higher wavelengths (Bastian 1994). We thus in the present case cannot observationally resolve any significant radial expansion of the magnetic field. Such a scenario is equivalent to type III producing electron beams propagating along thin coronal structures as observed in Trottet et al. (e.g. 1982); Pick et al. (e.g. 2009), or having very small radial expansion of the magnetic field in the low corona. The expansion is much smaller than what would be expected for the inner heliosphere, where the magnetic field expands as a cone with an angle around 40° (e.g. Steinberg et al. 1985).
The density of electron beams responsible for type III emission is believed to be small with Krucker et al. (2007) finding them 0.2% of the density of the downward propagating electron beams responsible for HXR emission above 50 keV. With an initial background density of 3 × 109 cm-3 providing the upper limit to the downward propagating electron beam, the upward propagating electron beam was injected with a density of nb = 104 cm-3 above 11 keV. However, observations show time dependent intensities of HXR photons which is related to the density of the inducing beam. Such results could indicate the potential need to consider a changing beam density. We note that Eq. (6) is independent of the density of the electron beam. The starting frequencies found from the upwardly propagating electron beam should thus be insensitive to rather large changes in beam density.
4.3. Numerical results
A high level of Langmuir waves is required to induce type III emission. We can estimate the starting height, htype III, from the simulations through the ratio of Langmuir wave spectral energy density to its initial thermal level W(v,r,t)/WTh(v,r,t = 0) or W/WTh. The first point in phase space when W/WTh exceeds a certain level can give us insight into how electron beams with different spectral indices become unstable.
The numerical results are presented in Fig. 6 for a variety of different W/WTh levels. By assuming Langmuir waves produce radio emission when they reach a certain level of W/WTh, we can treat the curves in Fig. 6 in a similar manner to the observational results. By applying a linear fit to each curve, we can obtain an estimate of the initial simulated acceleration region height and size using Eq. (6). As we know the actual initial simulated values for hacc and d, these estimates allow us to check how accurate the method is for obtaining good estimates. Such a fit also provides a numerical check for the simplified analytical relation Eq. (6) represents. We find the closest fit to the simulated hacc and d comes from the line where W/WTh = 105 giving hacc = 43.5 ± 5 Mm and d = 12.4 ± 0.6 Mm. These variables are within 20% and 15% of the original numerical values respectively.
Fig. 6
Heights corresponding to high levels of Langmuir waves from an unstable beam with density 104 cm-3. Symbols and colours correspond to different levels of Langmuir wave growth. Low levels (10 W/WTh) correspond to spontaneous emission of waves. High levels correspond to beam-plasma instability.
Fig. 7
Top: electron velocity spectral index plotted against the first phase velocity at which Langmuir waves exceed the threshold W/WTh = 105. Bottom: electron velocity spectral index plotted against the onset time required for the electron beam to induce Langmuir waves exceeding the threshold W/WTh = 105.
The results in Fig. 6 show a small variation between the heights corresponding to 103 < W/WTh < 106. Provided there are enough electrons to generate sufficient Langmuir waves for radio emission, a change in the beam density has minimal effect on the starting height htype III. Increasing or decreasing the beam density by one order of magnitude changed the inducing height of W/WTh = 105 by at most 14% when α = 6 with a mean over all spectral indices of 3%. Changing the beam density will only vary the level of Langmuir waves which are produced upon the electron beam becoming unstable. This result confirms the density independence of Eq. (6) where instability of the electron beam is mainly dependent upon the spectral index and size of the electron cloud.
The ratio W(v,r,t)/WTh(v,r,t = 0) also provides information regarding the Langmuir wave phase velocities and onset times when the waves exceeds certain thresholds. As electrons resonantly interact with Langmuir waves, the phase velocity of the Langmuir waves conveys information regarding velocities of the inducing electrons. The phase velocities corresponding to the points in Fig. 6 get smaller as the electron spectral index increases (softer spectrum). An example of the velocity variation is presented in Fig. 7 for the level W/WTh = 105. Similarly the time required for the beam to induce Langmuir waves at a certain level increases for larger spectral index (Fig. 7). Beams with larger spectral indices (with the same beam density) have less high energy electrons. We thus expect Langmuir wave emission to be induced by lower energy electrons which take longer to become unstable.
We can explore how the inclusion of an expanding magnetic field would change the simulation results. By ignoring the increase in radio source size at lower frequencies from NRH resolution and scattering we can assume the doubling of size between 432 and 237 MHz is because of a radially expanding magnetic field. Using the assumed density model the magnetic field would then expand as a cone with an angle of θ = 6°. By then assuming an acceleration site size which is as wide as it is long, we can constrain r0 in Eq. (7) to be 30 Mm below the solar surface. Running the simulations and using the same method described above gives estimations of hacc and d which are 12% and 40% of their original values. The expanding magnetic field causes the electron beam to induce a high level of Langmuir waves further away from the acceleration site. The frequencies corresponding to these heights do not agree as well with the observed starting frequencies of the type III bursts.
5. Discussion and conclusions
We used simultaneous observations of radio and hard X-ray emission during a solar flare to gain insight about the acceleration region of energetic electrons. With a simple model we have shown through an analytical relation how the starting height of type III emission and the spectral index of the electron beam can be related to the height and vertical extent of an acceleration region. By combining HXR spectral information with the starting frequencies of the type III bursts, we have derived for our event an estimate on the acceleration site height and size of hacc = 52 ± 21 Mm and d = 10.5 ± 1.6 Mm respectively. We have also used self-consistent numerical simulations of an electron beam which can induce Langmuir waves in a background coronal plasma. The simulations checked our predicted acceleration region values and allowed us to explore unknown parameters of the electron beam and Langmuir wave distributions.
The value found for hacc agrees with values in the range 20−50 Mm, deduced from electron time-of-flight analysis for HXR emission (Aschwanden 2002). This scenario indicates an acceleration region in the corona well above where SXR are imaged. The error on hacc is quite large but within the 95% range of 2-sigma the acceleration region remains within the corona. The value found for d is roughly an order of magnitude higher than previously found before in Aschwanden et al. (1995a). Assuming the relation in Eq. (6) the acceleration size in Aschwanden et al. (1995a) would not be able to produce significantly varying starting frequency of type III emission given a static acceleration site. Such a small acceleration site predicted by Aschwanden et al. (1995a) may be relevant for type III radio bursts when very little or no evolution of the starting frequency can be observed.
Using the estimates for hacc and d we ran self-consistent numerical simulations of an electron beam able to resonantly induce Langmuir waves in the background coronal plasma. We analysed the distance required for a large magnitude of Langmuir waves to be induced through beam instability for a variety of initial beam spectral indices. A linear fit to the initial beam spectral index and the height associated with strong Langmuir wave production gave a good estimation of the initial acceleration region height (within 20%) and the initial acceleration region size (within 15%) . The result fits with the analytical predictions from Eq. (6) and hence the relation is a powerful diagnostic tool for flare acceleration site properties. In line with the analytical equation the electron beam instability criteria was significantly dependent upon α and d and almost independent on the beam density, which was confirmed by numerical simulations. The simulations also gave an estimate of W/WTh ≥ 105 as the magnitude of Langmuir waves required to produce coherent radio emission. The discrepancies found in the acceleration region properties are due to additional terms present in the numerical simulations which were not present for the simple analytical expression.
It is also possible to explore how a different assumed initial electron beam distribution in space will affect our results. Initially in Eq. (1) we assumed a tent distribution for the electrons in space. We now consider an initial electron beam distribution which is Gaussian distributed in space such that (11)The instability criteria for this distribution was already discussed in Mel'Nik & Kontar (1999) and, assuming small collisional damping, gives the relation (12)The dependence of htype III on the square root of the spectral index originates from the r2 in the exponential for the electron distribution function. Unfortunately the observational errors on electron beam spectral index were too large to distinguish between the two models (Eqs. (1) and (11)). Even without observational error estimates such a fit to the data gives hacc = 33 ± 51 Mm and d = 22 ± 7 Mm which is not defined. More detailed observations are thus needed to differentiate between different initial electron distributions in space.
Another assumption we considered was a static acceleration site during the entire event. Kane & Raoult (1981) considered a moving acceleration site which decreased in altitude to explain why a type III burst's starting frequency increased with time. Assuming the magnetic nature of reconnection, any source movement would typically be at the Alfven velocity. At heights around 100 Mm, this is typically around 1 Mm s-1 (Arregui et al. 2007). The Alfven velocity is too slow to account for the varying starting frequencies of the type III emission observed in the April 15th flare considered. Moreover, the acceleration region would have to move upwards and downwards to account for the evolution of the starting frequencies. Our results do not rule out the acceleration region moving in altitude but this will probably not be the dominant process for determining dynamic type III starting frequencies on a time scale of seconds.
Flares associated with the same active region responsible for the 08:51 UT flare on the April 15th 2002 have been analysed previously. Sui & Holman (2003) found a coronal HXR source above the loop-top HXR source during another flare around 23:00 UT on the same day. The high coronal HXR source was initially detected at an altitude of 25 Mm and moved with a speed of 0.3 Mm s-1 up to an altitude of 40 Mm as the HXR flux increases. Moreover, the higher energy photons (15 − 16 keV) are detected at lower altitudes than the low energy photons (10 − 11 keV). This is indicative of an electron beam streaming down from a high acceleration region with high energy electrons having a larger stopping distance than low energy electrons. Such a scenario fits with the derived high acceleration region hacc ≈ 50 Mm we found in this study. A similar result was found for other high coronal sources (Liu et al. 2008, 2009) where high energy photons are imaged at lower altitudes than low energy photons.
In conclusion, we stress that simultaneous HXR and radio observations are a tool to estimate the otherwise unmeasurable sizes of the acceleration site. The results from our first trial of the relation given by Eq. (6) suggest that this size can be ≈ 10 Mm located at height ≈ 50 Mm, occupying a substantial fraction of the corona. The size is larger than the HXR sources which are typically observed with RHESSI and in the range between a few Mm up to a few tens of Mm (Emslie et al. 2003). We hope to continue this avenue of research by extending it to more events to build a statistical picture of flare acceleration characteristics. Future studies should also have a higher flux of HXR to better constrain the deduced electron beam spectral index.
Hamish Reid acknowledges the financial support of the SOLAIRE Network (MTRN-CT-2006-035484). Nicole Vilmer acknowledges support from the Centre National d'Études Spatiales (CNES) and from the French program on Solar-Terrestrial Physics (PNST) of INSC/CNRS for the participation to the RHESSI project. Eduard Kontar acknowledges financial
support from a STFC rolling grant and STFC Advanced Fellowship. Financial support by the Royal Society grant (RG090411) is gratefully acknowledged. The overall effort has greatly benefited from support by a grant from the International Space Science Institute (ISSI) in Bern, Switzerland. Collaborative work was supported by a British council Franco-British alliance grant. The NRH is funded by the French Ministry of Education, the CNES and the Région Centre.
- Arregui, I., Andries, J., Van Doorsselaere, T., Goossens, M., & Poedts, S. 2007, A&A, 463, 333 [NASA ADS] [CrossRef] [EDP Sciences] [Google Scholar]
- Arzner, K., & Benz, A. O. 2005, Sol. Phys., 231, 117 [NASA ADS] [CrossRef] [Google Scholar]
- Aschwanden, M. J. 2002, Space Sci. Rev., 101, 1 [NASA ADS] [CrossRef] [Google Scholar]
- Aschwanden, M. J., & Benz, A. O. 1997, ApJ, 480, 825 [NASA ADS] [CrossRef] [Google Scholar]
- Aschwanden, M. J., Benz, A. O., Dennis, B. R., & Schwartz, R. A. 1995a, ApJ, 455, 347 [NASA ADS] [CrossRef] [Google Scholar]
- Aschwanden, M. J., Montello, M. L., Dennis, B. R., & Benz, A. O. 1995b, ApJ, 440, 394 [NASA ADS] [CrossRef] [Google Scholar]
- Aschwanden, M. J., Schwartz, R. A., & Dennis, B. R. 1998, ApJ, 502, 468 [NASA ADS] [CrossRef] [Google Scholar]
- Bastian, T. S. 1994, ApJ, 426, 774 [NASA ADS] [CrossRef] [Google Scholar]
- Benz, A. O., Barrow, C. H., Dennis, B. R., et al. 1983, Sol. Phys., 83, 267 [NASA ADS] [CrossRef] [Google Scholar]
- Benz, A. O., Grigis, P. C., Csillaghy, A., & Saint-Hilaire, P. 2005, Sol. Phys., 226, 121 [NASA ADS] [CrossRef] [Google Scholar]
- Brown, J. C. 1971, Sol. Phys., 18, 489 [NASA ADS] [CrossRef] [Google Scholar]
- Brown, J. C., Emslie, A. G., Holman, G. D., et al. 2006, ApJ, 643, 523 [NASA ADS] [CrossRef] [Google Scholar]
- Dennis, B. R., Benz, A. O., Ranieri, M., & Simnett, G. M. 1984, Sol. Phys., 90, 383 [NASA ADS] [CrossRef] [Google Scholar]
- Drummond, W. E., & Pines, D. 1962, Nucl. Fusion Suppl., 3, 1049 [Google Scholar]
- Emslie, A. G., Kontar, E. P., Krucker, S., & Lin, R. P. 2003, ApJ, 595, L107 [NASA ADS] [CrossRef] [Google Scholar]
- Ginzburg, V. L., & Zhelezniakov, V. V. 1958, SvA, 2, 653 [Google Scholar]
- Grigis, P. C., & Benz, A. O. 2004, A&A, 426, 1093 [NASA ADS] [CrossRef] [EDP Sciences] [Google Scholar]
- Hamilton, R. J., Petrosian, V., & Benz, A. O. 1990, ApJ, 358, 644 [NASA ADS] [CrossRef] [Google Scholar]
- Hannah, I. G., Kontar, E. P., & Sirenko, O. K. 2009, ApJ, 707, L45 [NASA ADS] [CrossRef] [Google Scholar]
- Kane, S. R. 1972, Sol. Phys., 27, 174 [NASA ADS] [CrossRef] [Google Scholar]
- Kane, S. R. 1981, ApJ, 247, 1113 [NASA ADS] [CrossRef] [Google Scholar]
- Kane, S. R., & Raoult, A. 1981, ApJ, 248, L77 [NASA ADS] [CrossRef] [Google Scholar]
- Kane, S. R., Benz, A. O., & Treumann, R. A. 1982, ApJ, 263, 423 [NASA ADS] [CrossRef] [Google Scholar]
- Kerdraon, A., & Delouis, J. 1997, in Coronal Physics from Radio and Space Observations, 483, 192 [Google Scholar]
- Kontar, E. P. 2001, A&A, 375, 629 [NASA ADS] [CrossRef] [EDP Sciences] [Google Scholar]
- Kontar, E. P., & Jeffrey, N. L. S. 2010, A&A, 513, L2 [NASA ADS] [CrossRef] [EDP Sciences] [Google Scholar]
- Kontar, E. P., & Reid, H. A. S. 2009, ApJ, 695, L140 [NASA ADS] [CrossRef] [Google Scholar]
- Krucker, S., Kontar, E. P., Christe, S., & Lin, R. P. 2007, ApJ, 663, L109 [Google Scholar]
- Krucker, S., Oakley, P. H., & Lin, R. P. 2009, ApJ, 691, 806 [NASA ADS] [CrossRef] [Google Scholar]
- Lifshitz, E. M., & Pitaevskii, L. P. 1981, Physical kinetics, ed. E. M. Lifshitz, & L. P. Pitaevskii [Google Scholar]
- Lin, R. P., Dennis, B. R., Hurford, G. J., et al. 2002, Sol. Phys., 210, 3 [Google Scholar]
- Liu, W., Petrosian, V., Dennis, B. R., & Jiang, Y. W. 2008, ApJ, 676, 704 [NASA ADS] [CrossRef] [Google Scholar]
- Liu, W., Wang, T., Dennis, B. R., & Holman, G. D. 2009, ApJ, 698, 632 [NASA ADS] [CrossRef] [Google Scholar]
- Markwardt, C. B. 2009, in ASP Conf. Ser., 411, 251 [Google Scholar]
- Mel'Nik, V. N., & Kontar, E. P. 1999, New Astron., 4, 41 [NASA ADS] [CrossRef] [EDP Sciences] [Google Scholar]
- Melrose, D. B. 1980, Plasma astrohysics. Nonthermal Processes in Diffuse Magnetized Plasmas (Gordon and Breach) [Google Scholar]
- Messmer, P., Benz, A. O., & Monstein, C. 1999, Sol. Phys., 187, 335 [NASA ADS] [CrossRef] [Google Scholar]
- Paesold, G., Benz, A. O., Klein, K., & Vilmer, N. 2001, A&A, 371, 333 [NASA ADS] [CrossRef] [EDP Sciences] [Google Scholar]
- Pick, M., & Vilmer, N. 2008, A&ARv, 16, 1 [NASA ADS] [CrossRef] [MathSciNet] [Google Scholar]
- Pick, M., Kerdraon, A., Auchère, F., et al. 2009, Sol. Phys., 256, 101 [NASA ADS] [CrossRef] [Google Scholar]
- Press, W., Flannery, B., Teukolsky, S., & Vetterling, W. 1992, Numerical Recipes in C: The Art of Scientific Computing (Cambridge University Press) [Google Scholar]
- Raoult, A., Pick, M., Dennis, B. R., & Kane, S. R. 1985, ApJ, 299, 1027 [NASA ADS] [CrossRef] [Google Scholar]
- Raulin, J., Vilmer, N., Trottet, G., et al. 2000, A&A, 355, 355 [NASA ADS] [Google Scholar]
- Reid, H. A. S., & Kontar, E. P. 2010, ApJ, 721, 864 [NASA ADS] [CrossRef] [Google Scholar]
- Ryutov, D. D. 1969, JETP, 57, 232 [Google Scholar]
- Steinberg, J. L., Hoang, S., & Dulk, G. A. 1985, A&A, 150, 205 [NASA ADS] [Google Scholar]
- Sui, L., & Holman, G. D. 2003, ApJ, 596, L251 [NASA ADS] [CrossRef] [Google Scholar]
- Trottet, G., Pick, M., House, L., et al. 1982, A&A, 111, 306 [NASA ADS] [Google Scholar]
- Vedenov, A. A., Lelikhov, E. P., & Sagdeev, R. Z. 1962, Nucl. Fusion Suppl., 2, 465 [Google Scholar]
- Vilmer, N., Krucker, S., Lin, R. P., & The Rhessi Team. 2002, Sol. Phys., 210, 261 [NASA ADS] [CrossRef] [Google Scholar]
All Figures
Fig. 1
The morphology of the April 15, 2002 solar flare. Background is SOHO/EIT 195 image. The small red contour lines at the base of the plasma loops on the left correspond to HXR photons imaged by RHESSI in the 15 − 30 keV range. The large contours on the right hand side correspond to NRH radio images at frequencies 432 MHz (blue), 327 MHz (orange), 236 MHz (pink), 164 MHz (yellow).
|In the text
Fig. 2
Time evolution of the radio and HXR fluxes for the April 15, 2002 solar flare between 08:51 and 08:54 UT. The top panel is the Phoenix-2 radiospectrometer data on a log scale between the frequencies 160 and 700 MHz. The middle panel is the Nançay radioheliograph flux time profiles observed at 5 discrete frequencies from 164 to 432 MHz. The bottom panels are the RHESSI HXR counts/second at the three energy ranges 6−12, 12−25 and 25−50 keV.
|In the text
Fig. 3
HXR spectral index and frequency spectra of the type III burst for two different time periods in the April 15, 2002 event. The starting frequencies are plotted as red stars connected by dashed lines. The HXR spectral indices are plotted as 2 s green bars with error bars in the middle of their integration time.
|In the text
Fig. 4
Scatter plot of the HXR photon spectral index vs. the starting frequencies of the type III burst. The one sigma observational errors on both spectral index and starting frequency are shown.
|In the text
Fig. 5
Scatter plot of electron beam spectral index in velocity space, α, calculated from the HXR photon spectral index vs. the distance above the photosphere associated with the starting frequencies of the type III burst. The one sigma observational errors on both spectral index and height are shown. The green dashed line is a linear fit to the data including observational error with the green dotted lines showing the extremes of the fit.
|In the text
Fig. 6
Heights corresponding to high levels of Langmuir waves from an unstable beam with density 104 cm-3. Symbols and colours correspond to different levels of Langmuir wave growth. Low levels (10 W/WTh) correspond to spontaneous emission of waves. High levels correspond to beam-plasma instability.
|In the text
Fig. 7
Top: electron velocity spectral index plotted against the first phase velocity at which Langmuir waves exceed the threshold W/WTh = 105. Bottom: electron velocity spectral index plotted against the onset time required for the electron beam to induce Langmuir waves exceeding the threshold W/WTh = 105.
|In the text
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The innovative TT-Sense®, thrust and torque sensor is a unique measurement system for propulsion efficiency. It monitors the efficiency of the propeller and fouling of the vessels hull. The optical sensors use nanotechnology to measure shaft power and actual thrust generated by the propeller, resulting in a total efficiency overview of the propulsion system.
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April 22, 2014 was Earth Day and in honour of that, I've been showcasing photos of National and Provincial Parks of British Columbia and Canada on my Facebook page. In a happy coincidence, I also found out it was National Parks Week in the US.
While seeking photos of Provincial and National Parks I realized that despite traveling through most of the country, I haven't been to many parks outside of BC. I've visited a lot of parks in British Columbia, mostly through random hiking adventures and the occasional camping experience.
Here is a collection of some of the most memorable parks I've visited in British Columbia. Some of these I featured on my Facebook page this past week, plus I've added a few more favourite parks from this beautiful province that I get to call home.
Myra-Bellevue Provincial Park
Last summer while in the Okanagan I explored the Myra Canyon Trestle Bridges which is a part of the Myra-Bellevue Provincial Park. I really enjoyed exploring all the trestle bridges and seeing what can happen when a community comes together when disaster strikes. The park itself is very large and the canyon is only a small portion of the park. There are a number of other trails that you can hike and the park is open for horses and horseback riding as well.
E.C. Manning Provincial Park
I've gone camping a number of time at Manning Park. Located a 3 hours drive from Vancouver, there is plenty to do in this park. There are many camping areas, but be warned, the ones along Lightning Lake go the fastest. If full fledged camping isn't your thing, there are also cabins (and a whole resort complex) that you can book. These go even faster so book early.
There is plenty to do in the park from hiking to hanging out by the lake. There is also the option to rent boats, kayaks and canoes. Fishing is also possible within the park's rivers and lakes. You can take a drive up to Cascade Lookout and get a beautiful view of the whole park. While I've only gone in the summer, the park also has a mini ski hill which you can enjoy in the winter. It looks like it would be a good place for a beginner to pick up a winter sport.
MacMillan Provincial Park
MacMillan Provincial Park is one of my favorite provincial parks simply because you can visit Cathedral Grove and hug a tree. 800 year old Douglas fir trees tower above with the biggest reaching 75 m (250 ft) tall and 9 m (29 ft) wide. That's a massive tree! You feel so small up against it.
Located on Vancouver Island, Cathedral Grove is a must visit, especially if you're en route to Tofino or Ucluelet on the west side of the island. The highway runs right through the middle of the park so you can't miss it. The south side is where you will find the biggest tree and to the north you can wander through ancient Western red cedars. The paths are wide and easy to walk, making it accommodating for all. Even if the weather is crappy like it was during my visit, it's still so gorgeous.
Before you enter the park, make sure you stop off at the Coombs General Store and grab some ice cream. You'll know you're there when you spot the goats on the roof.
Pacific Rim National Park
The Pacific Rim National Park runs along the left coast of Vancouver Island. Known for its beautiful coast lines and rainforests, the park is split up into three areas: Long Beach, the Broken Group islands and the West Coast Trail. I've only visited the Long Beach portion of the park which is located a short drive away from Tofino and Ucluelet.
The beaches in this area are long with waves coming in from the open Pacific Ocean making it a mecca for surfing enthusiasts. Even if you're just learning, there are plenty of businesses in the area who offer lessons. I visited during a grey and wet April and opted to stay out of the water, but I'll have to go back one day and try my hand at some surfing!
Beyond the beach, there are lots of trails and hikes available. The park provides interpretive programs as well which introduces you to the flora and fauna in the area and explore some of the park's history. There are options to camp directly in the park, or you can stay in nearby Tofino or Ucluelet.
For more about the Pacific Rim National Park, check out the posts at Wanderlust Megan. She went on a solo camping trip (!!!) last summer to the region and has shared a lot of her experiences in her blog.
Desolation Sound Marine Provincial Park
Visiting Desolation Sound Marine Provincial Park is probably the coolest provincial park I've visited, all because of the circumstance that surrounds it. In high school (yes I'm talking years ago, but it's too memorable to not mention), I was given the opportunity to learn how to sail in Desolation Sound. The name is no joke, it really is desolate, but so serene and beautiful. Desolation Sound is located on the Sunshine Coast of BC, 150 km north of Vancouver.
I was on a boat with 5 of my friends and an instructor learning how to sail and navigate. At the end of it I came away with a boating license. I like to joke that I learned how to drive a boat before I even sat behind the wheel of a car. Not that I've been boating since. I also found out during that trip that I don't like being on a small (if you call 40 ft small) boat.
The only way to see this park is on the water either by boat or kayak, the latter you can rent from nearby Powell River. The park has more than 60 km of shoreline, several islands and numerous small bays and picturesque coves. There are plenty of trails and waterfalls to explore. There is an option to camp in the park as well. I would love to return to the area one day. It's so beautiful.
Porteau Cove
For those unable to sail and visit the coves of Desolation Sound, you have Porteau Cove Provincial Park. An hours drive out of Vancouver, en route to Whistler, lies Porteau Cove on the most southerly fjord in North America.
I've only been here during the day, but there are options for camping or renting a cabin as well. You can go swimming, explore the beach and pier area or go windsurfing. This is also a popular place for scuba divers. Two ships were sunk in the area to provide interest for divers and to encourage marine life.
Which of these would you most like to visit? Do you like camping or do you prefer to stay where there is running water?
If you're new to Pack Me To, welcome! Stay on top of my adventures on Facebook and following me on Twitter & Instagram.


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Following are the details of the news:
As part of efforts to support the nation's pharmaceutical industry through the commercialisation of research findings by the Raw Materials Research and Development Council (RMRDC) partnering with International Center for Ethnomedicine and Drug Development (InterCEDD) to establish a small scale plant for production of Lovastatin, an Active Pharmaceutical Ingredient (API) for the production of drugs used to treat coronary heart disease.
The DG/CEO RMRDC, Prof. Doko Ibrahim made this known in a meeting organized by the Council at NASRDA to fine tune modalities of the partnership for the establishment of the plant to produce Lovastatin as an Active pharmaceutical Ingredient derived from mushroom.
The plant, which will be the first of its kind in Nigeria, will be sited in National Space Research and Development Agency, (NASRDA) Abuja where RMRDC'S process equipment demonstration center is domiciled, the DG said.
Professor Ibrahim said the aim of establishing a small scale plant for the production of Lovastatin as an API is to support the pharmaceutical industry to source this major pharmaceutical raw material locally. He emphasized that the product is the first indigenously produced Active Pharmaceutical Ingredient (API) in the Country.
The RMRDC Boss also said that the facility that will house the equipment is ready at RMRDC Technology and Innovation Center, NASRDA, Airport Road, Abuja. He reiterated that RMRDC is working hard towards the procurement of the plant.
The DG said explained that it will be appreciated if InterCEEDD could take up the responsibility of managing the plant, though InterCEDD will take equity in the project while RMRDC will take the lead.
Earlier, the Chairman InterCEDD/BDG, Prof. Maurice Iwu in his response, commended the DG/CEO RMRDC for the many successes he has achieved since his assumption of office. He cited the instance of the R&D work by the Council on lovastatin production, which earned it the first position in the 2020 Technology and Innovation Exposition held in Abuja. He also stated that the DG/CEO RMRDC and the Council intervened promptly in solving the problems of Covid – 19 by responding to the request for local sourcing of Andrographis paniculata for the mass production of IHP Detox tea.
Speaking further, the former Independent National Electoral Commission (INEC) Boss said the DG had helped the Country immensely with his prompt response, and that considering many other vital roles he has been playing towards the development of local raw materials for the industries, his leadership style should be applauded. He further said that his organization is very much committed to partnering with the RMRDC in this project and to see to its logical completion. He added that by the time the product is 80% ready, Nigerians would be eager to subscribe to it because it is a product that would stand the test of the time.
Also speaking, Prof. Elijah Sokomba, National Coordinator InterCEDD added that the Covid – 19 products (IHP Detox tea) was undergoing clinical trials at University of Lagos and would be fully registered with the National Agency for Food and Drug Administration and Control (NAFDAC) after the exercise. He also appreciated the DG/CEO RMRDC and the Council for the forward-looking approach to issues and development of many industrial raw materials.
In his own contribution, Pharm. Bola Yusuf, the consultant advised that the Good Manufacturing Practices (GMPs) Section of the National Agency for Food and Drug Administration and Control (NAFDAC) should be invited to inspect the site and see the flow diagram of the plant before site modification. He said this would facilitate the registration of the product by NAFDAC.
Lovastatin is a naturally occurring drug found in food such as oyster mushroom and red yeast rice. It is member of the drug – class of statins used in combination with diet, weight loss and exercise for lowering cholesterol in individuals with hypercholesterolaemia, to reduce the risk of this cardio- vascular disease, which is a known killer disease in Nigeria today.
The oyster mushroom contains about 2.8% lovastatin. The amount depends on fruiting size, age and substrate composition.
Lovastatin is a white non-hygroscopic crystalline powder that is soluble in water and sparingly soluble in ethanol, methanol and acetonitrile. It is a secondary raw material and is the active component, compounded with other drug carriers and nutritional elements for the formulation of some statin drugs. Statin drugs are a popular way of lowering the risks of heart attack and stroke. The drugs work to hinder the production of an enzyme in the liver that makes cholesterol in the body. They are sold under different names and come in varying doses.
There are very few oyster mushroom cultivators in Nigeria. The technology of mushroom cultivation has not been widely publicized. Moreover, awareness created by the relevant government agencies such as the Raw Materials research and Development Council has been mainly on the cultivation of mushroom for culinary purposes, job and wealth creation.
Not much has been projected on Oyster mushroom as a source of secondary raw material for the Pharmaceutical industries in the production of anti – lipidemics.
The relevance of Lovastatin project to the Pharmaceutical sector of the nation's economy cannot be over-emphasized. In line with Council's mandate of industrialization through utilization of local raw material resources, it is imperative that Council intervenes in the local production of statin drugs from locally cultivated mushrooms. This will enhance commercialization of mushroom cultivation, create jobs and provide alternative source of raw materials for the pharmaceutical industries. Furthermore, statistics obtained from NAFDACPRS shows an increasing trend in the amount spent annually on the importation of statins drugs. It is also evident that the demand for the drug is increasing by the year; therefore, local production should be explored, since statin drugs are wholly imported into the country. This will save foreign exchange, reduce poverty, create jobs, and build capacity in mushroom production and lovastatin isolation technologies.
The project therefore meets the requirements for the goals of local raw material utilization, import substitution and commercialization.


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14 thoughts on "Comments"
We are all very happy with our wonderful trip to Uzbekistan.
Best regards!!!Thank you!
Ich möchte mich im Namen unserer Gruppe bei Ihnen für die perfekte Organisation unserer Reise durch Usbekistan herzlich bedanken. Das gesamte Programm mit dem Ablauf, den Unterkünften, Transport und Verpflegung hat unsere Erwartungen nicht nur erfüllt, sondern übertroffen !
Für den weiteren Erfolg und die Entwicklung Ihres schönen Landes und Ihrer Agentur wünschen wir Ihnen alles Gute.
Mit freundlichen Grüßen
I organized a group in Uzbekistan last November and used Olympic Tour as incoming operator. The gentle Gulya who followed the organization of our group was impeccable, attentive and very patient. She has organized a perfect tour. The hotels were all up, excellent buses and drivers, the restaurants always varied. Our guide, Mrs. Nigora Alieva, was superb, she is prepared and especially kind and always attentive to all requests. I can say that with the Olympic Tour, the trip was a success.
Thanks and greetings from the whole group
Rafaella Amendola
RENDEZ VOUS Travel Agent
Venezia – ITALY
We were a Group of 6 persons from Germany. Olympic Tour organized for us an excellent tour through Uzbekistan (Tashkent, Khiwa, Buchara, Samarkand, Aydarkul Lake, Shachrisabz, Kokand, Margilan) and subsequent trekking in Kyrgisistan (Chychkan Gorge and Ala Acha National Park), as well as the visit of Bishkek). Guides were excellent, service was very good, very reliable. All was according to plan. A wonderful and very interesting experience!


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Learn everything a bear cub needs to know at bear school!
Can you growl like a bear so that the whole forest trembles, or hurtle down a chute as fast as lightning?
Can you crawl through a narrow tunnel without getting tired? Or balance on logs without falling off?
Welcome to bear school!
On the bear school curriculum: climbing, balancing, jumping, sliding, enjoying the view, tracking and hiding.
The playground is freely accessible to everyone and is located directly at the middle station of the Arosa-Weisshorn cable car.


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What animal would you be if your finger bones grew so long that they reached
your feet? Or what if you had no leg bones but kept your arm bones?
picture book will keep you guessing as you read about how human skeletons are
like—and unlike—those of other animals.
At this event you'll have a chance to explore bones in person; Sara will bring
a collection to show off.
Sara Levine is an assistant professor of biology at Wheelock College and a
veterinarian. Her science books for children include Bone by Bone: Comparing Animal
Skeletons, Tooth by Tooth: Comparing Fangs, Tusks and Chompers, and Fossil
by Fossil: Comparing Dinosaur Bones.
Her books have received a number of recognitions including AAAS/Subaru
SB&F Prize for Excellence in Science Books, Utah Beehive Book Award, Bank
Street College Best Children's Book of the Year, and Cook Prize finalist for
best STEM picture book.
Please register to attend this FREE event here.


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The Regional Trial Court of Quezon City issued a decision to CONFIRM the Final Award dated December 29, 2014 rendered by the Appeals Panel in Arbitration Case No. UNC 141/CYK, entitled Maynilad Water Services, Inc. vs. Metropolitan Waterworks and Sewerage System (MWSS) and Regulatory Office on August 30, 2017, under Civil Case No. R-QZN-15-06702 CV.
The MWSS-Regulatory Office will exhaust all legal remedies, including filing a Motion for Reconsideration, in order to protect the interest of the public.


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Experience all the excitement of activities on, in and around water,
Sliding jumps, abseiling, natural chutes and waterfall pools: if you like big thrills, you'll love canyoning. Most of the gorges in the Val d'Aran present no special difficulties, which makes them ideal for anyone who wants to try the sport for the first time, or for families with children looking for a day of aquatic adventures. Companies operating in the area also organise trips to more difficult canyons.
The Garonne river is the perfect place to experience a white water rafting trip downstream, or other less well-known but no less exciting sports, such as hydrospeed, canoeing or kayak surfing.
In spring the rivers and lakes of the Val d'Aran become the ideal location for angling enthusiasts from all over the world.


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Eleven-year-old Oliver Stepanic hadn't played a sport since kindergarten, but this winter, he decided to try basketball as a "personal growth opportunity," says dad Steven. He set some goals for the season—an aptly-named "bucket list" for his time in YMCA Youth Sports. "[He wanted to] score a basket, box someone out, get a rebound, and steal a ball," Steven says. "He worked hard and was able to accomplish all of his goals during the season."
Oliver had a fun perk to playing, as well—his dad was the volunteer coach. "I liked being able to play a sport with my dad as the coach and being part of a team with other kids," Oliver shares. "I am proud of myself for pushing outside of my comfort zone and trying something new."
In addition to seeing his own son achieve so many of his personal goals, Steven had the chance to witness all of his players grow through the season. "I was proud to watch the players execute plays and strategies they learned during practice," Steven says. "There was one game where our team showed a tremendous amount of heart against a seasoned opponent. It was inspiring to see how they took on the challenge with a positive attitude, team spirit, and tenacity from the opening tip-off to the final buzzer."
Before coaching, Steven didn't realize how invested he would become in developing his team. "My goal was for every kid to have the opportunity to play, meet their personal goals, and grow as a player. Being able to coach my son's team gave him the confidence to take a risk by trying a team sport. It was a unique experience to celebrate every success from practice to the sidelines. These are memories that are irreplaceable."
Learn more about YMCA Youth Sports at ymcamidtn.org/youth-sports.


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DermaClear Skin was inspired by my own personal struggle with acne. I had skin issues from teenage to adult year. My skin was frustratingly temperamental even with hormonal breakouts. I was constantly searching for a resolution. No products seemed to work and if they did, it was only for a short time before reverting back to how it had been before. I was jaded dealing with breakouts which always seemed to occur at the worst time. I found myself consistently covering blemishes and scars. I had no idea how liberating it felt be comfortable in my own skin without makeup or concealer.Then I started going to an esthetician and it opened an door for natural holistic approaches. For 3 years I tried numerous methods including essential oils and exclusive herbs until I found one that not only worked for me but for my friends as well. I knew I had created something life changing for all skin types. I had a product that visibly improved acne in 2-3 days and cleared acne/blemishes just in weeks. I knew I had to pay it forward and help others conquer acne once and for all.
Your skin looks great. But DermaClear can make it look it's BEST.


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Hitech Properties is an award-winning organization in the real estate sector which was established in 2002. Since its inception, the company has successfully completed prestigious projects. Hitech Properties is a venture by the Hitech Family which is incorporated and managed by its family members. The company deals with the development of Commercial complexes, Flats, Bungalows, and Multiple Floor Buildings.
If you are looking for affordable projects, then Hi-Tech Properties are the best option for you. With a vast client base, we have developed a massive repudiation in the market. We are organised with skilled workers and highly qualified professionals to deliver the best quality project to the client.Read more


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Check back regularly here for Sandbox and home improvement tips and tricks to make sure you get the most out of your next Sandbox!
We help you to figure out the strategy
You will need to be kept informed when it comes to Sandbox in Kirbyville, MO. You should not go in blindly, and you should know what to expect. You're not going to deal with any sort of unexpected surprises when you deal with Apt Sandbox. Step one will be to call us today by dialing 866-840-7884 to arrange your job. During this call, you'll get your questions addressed, and we are going to set up a time to get started with services. We work together with you all through the whole project, and our staff is going to arrive on time and well prepared.
Apt Sandbox is going to be there for all your expectations involving Sandbox in Kirbyville, Wyoming
You have a lot of reasons to rely on Apt Sandbox to meet your requirements concerning Sandbox in Kirbyville, MO. We have the greatest client satisfaction ratings, the highest quality supplies, and the most sensible and successful money saving techniques. We understand your expectations and ambitions, and we're there to assist you using our skills. Dial 866-840-7884 to reach Apt Sandbox and consider all your expectations about Sandbox in Kirbyville.


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Air filter replacement is one of the pillars of HVAC maintenance. Most of the problems heating and cooling units develop can be prevented by simply keeping the filter clean. Normally, it needs attention once every three months, though thicker filters generally take longer to clog and may only need to be disposed of once a year.
So what exactly happens if you don't change your system's air filter? Below are some of the problems that are likely to arise.
Inadequate Heating or Cooling
A dirty filter restricts the flow of air into the heating and cooling equipment. This can cause your furnace or air conditioner to suffocate, preventing it from producing enough conditioned air to reach the temperature set on the thermostat. As a result, your system will underperform, and you'll eventually start to feel uncomfortable.
Short Cycling
This phenomenon happens when a heater or AC turns on and off repeatedly. When a unit short cycles, it may stop running before reaching the desired temperature for the room. Normally, you can fix this by changing the thermostat's batteries, but if this fails then cleaning the air filter would be the next troubleshooting step.
Premature Equipment Failure
By neglecting a filthy filter, you can compromise the integrity of the entire heating and cooling system. Sooner or later, something will begin acting up, ultimately causing the equipment to break down.
Poor Indoor Air Quality
Filters purify air by filtering out and trapping pollutants as it flows through the interior heating and cooling components of the HVAC, while other electrostatic varieties attract dust particles. But no air filter has an unlimited capacity; the dirtier they get, the less effective they become as an air cleaning solution.
Take HVAC Filter Replacement Seriously
If you encounter HVAC problems you can't solve by cleaning or changing the air filter, turn to Premier Comfort Heating and Air. Call us at (720) 613-5904 to request for service any time and day of the week.


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Client Spotlight – Front Rangers
Front Rangers is a junior cycling program in Colorado dedicated to developing young athletes' skills and passion for the sport. They approached Faster…
A Faster Way To Do
A powerful, affordable, complete sales & marketing platform.
With a full set of powerful features, unlimited users, and no long-term contract required, we make marketing automation easier than ever. We'll connect the marketing dots, track customers before you know their name, and tell you where they've been. But that's just the beginning. Let's build powerful automation workflows to send your customers personal, dynamic content based on their interests and behavior. Optimized marketing will drive more leads and convert more sales. Partner with Faster Solutions for affordable marketing automation at a fraction of the cost of competitors.
Select a breakdown that works best for you
We take the time to learn about your business and your target audience to provide the best user experience possible for both you and your customers.
Our design team follows the latest marketing trends and guidelines while they create graphics and images that take your website and advertising to the next level! We'll present you with solutions that meet your goals and exceed your expectations.Get a Demo
Front Rangers is a junior cycling program in Colorado dedicated to developing young athletes' skills and passion for the sport. They approached Faster…
Artificial Intelligence (AI) refers to the simulation of human intelligence in machines that are programmed to think and learn like humans. It is a…
In today's digital world, social media marketing plays a crucial role in building brand awareness, engaging with customers, and driving business…
We at Faster Solutions
want to take a
moment to say...
Hey, thanks!
For being our customer and letting us serve you in business, we wish to thank you. Without you, we wouldn't be here. We want to extend our sincerest gratitude to you for the opportunity you provide us through the work we are so lucky to do each day.
It's in each exchange with our customers that we truly understand how fortunate we are to have such a great group of clients to work with.
So THANKS for working with us and taking the time to read this. We hope as you continue through the rest of your day you know how appreciated you are.
– The Faster Solutions Team
Facebook, Instagram, Twitter, Snapchat, PPC Campaigns, YouTube, Vimeo, SEO, Google Business Listing, Linkedin, Indeed, and any other social media or Pay-Per-Click options currently available.


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[1] The rotation of crops with fast-growing tree, shrub, and herbaceous N-2-fixing legume species ( improved fallows) is a central agroforestry technology for soil fertility management in the humid tropics. Maize yields are increased following improved fallows compared with continuous maize cropping or traditional natural-fallow systems consisting of broadleaved weeds and grasses. However, the effect of these improved-fallow systems on N availability and N2O emissions following residue application has yet to be determined. Emissions from these systems not only have a detrimental effect on the environment, but are of additional concern in that they represent a potentially significant loss of N and a reduction in N-use efficiency. Emissions of N2O were measured from improved-fallow agroforestry systems in western Kenya, being characteristic of agroforestry systems in the humid tropics. Emissions were increased after incorporation of fallow residues and were higher after incorporation of improved-fallow legume residues (Sesbania sesban, Crotalaria grahamiana, Macroptilium atropurpureum) than natural-fallow residues ( mainly consisting of Digitaria abyssibica, Habiscus cannabinus, Bidens pilosa, Guizotia scabra, Leonotis nepetifolia, Commelina benghalensis). Following incorporation of Sesbania and Macroptilium residues (7.4 t dry matter ha(-1); 2.9% N) in a mixed fallow system, 4.1 kg N2O-N ha(-1) was emitted over 84 days. The percentages of N applied emitted as N2O following residue incorporation in these tropical agroforestry systems were of the same magnitude as in temperate agricultural systems. N2O (log(e)) emissions were positively correlated with residue N content (r = 0.93; P < 0.05), and thus the residue composition, particularly its N content, is an important consideration when proposing management practices to mitigate N2O emissions from these systems.
|Original language
|Article number
|Number of pages
|Global Biogeochemical Cycles
|Issue number
|Publication status
|Published - 26 Feb 2004
- agroforestry
- humid tropics
- improved fallows
- nitrous oxide
- residue quality
- soil mineral nitrogen
- land use change
- denitrification rates
- soil emissions
- release
- lignin
- mineralization
- legumes
- carbon
- litter
- decomposition


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Batties Association Brother Sun and Sister Moon
Is everything as it seems? Is the sky really blue? Do dogs like to smell each others bottoms to gauge their scent or do they just really like the smell of leftover poo? Join Drag Prince Sun and their little sister, Drag Princess Moon, in a fairy tale tent under the stars for an experience like no other. Through sensual storytelling, glittery puppets, and live music, learn to embrace yourself, your inner child and all your witchy powers. ★★★★ (PhoenixArtsClub.com).
This show was part of our 2019 Edinburgh Fringe Programme


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Haiku Lane
Taurus Necklace
Taurus- April 20- May 20
This art is done in collaboration with 2 am Illustrations.
14 karat gold vermeil (thick gold plating over sterling silver)
18 " singapore chain with extender. Tiny lab made Opal stone.
- Complimentary expedited shipping on orders over $125 CAD in Canada and the United States.
- All unworn and original condition products, excluding earrings, are eligible for return. See our Return Policy here.
- Haiku Lane uses high quality materials including 925 Sterling Silver and 14 Karat Gold Vermeil.
- Please follow our jewelry care recommendations to prolong the life of your jewelry.


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Clash Royale is a mobile strategy game from Supercell. As part of the gameplay, you have to manage the castle, as well as a squad of warriors in order to crush your opponent. Each unit, spell, skill or technique in this game is a card you must collect and improve in order to increase the characteristics of a certain hero. The characters available to the user have factions. Only you decide which tactics to adhere during confrontation. Framework of the project allows you to concentrate on online battles or immerse yourself in a confrontation with computer opponents. You have to think a lot about each round in both cases, since the opponents in the game are strong.
Overall Info
|121 Mb
|Mod Info
|- Unlimited Everything
- Private server
- Maps unlocked
|Requires Android
Clash Royale is one of the most famous games in its genre. Learn more about the main features of this wonderful project.
Participate in a variety of exciting modes
You can play Clash Royale in solo mode as well as in 2v2 battles. While playing solo, you need to defeat the main tower of the opponent using your units, fighting one on one. Two-by-two mode features four towers and each player can control his deck independently. We should also mention the opportunity to share emotions with other players after the match. It can be a funny face of the king, crying or laughing triumphantly, or a phrase. This attention to detail adds excitement and delight to the user at the same time.
Collect your unique collection of powerful cards
Both characters and special spells, abilities, skills of heroes in Clash Royale are ordinary collectible cards. You can build a deck of them, and then try your hand against a coach or a real player. At the same time, you get cards from the deck in a random way, which adds interest to the gameplay. You can improve each creature, spell or technique by collecting a certain number of specific cards. This, like opening the chests, takes time. Spend gold on improving cards, as well as buying the simplest chests. All characters, spells and techniques are subject to rarity gradation.
Build the strongest deck to smash your enemy
From the received cards in Clash Royale, you need to build a deck. It is not necessary to collect the entire collection of cards in order to become an effective duelist within the game. You just need to find your own fighting style, and then try to get only the necessary parts of your deck. There are exactly eight cards in the deck, each of which corresponds to a certain creature. You can see the characteristics of the fighters in cards description.
At the time of your turn, only four of the eight cards are available to you – after discarding one of them, another one comes to replace it. You get cards randomly, which also adds a little extra variety to the process.
Destroy opponents' towers and open epic chests
Your main goal in Clash Royale is to destroy the opponent's main tower using only your deck, reaction and ingenuity. Receive chests of various rarities after each match won. Ordinary chests have fewer cards and less gold, while epic or legendary chests have the rarest cards that can greatly enhance your deck. The card drops out randomly. Each chest has its own level. The higher it is, the more powerful cards fall out of it. In addition, the higher the arena level, the correspondingly cooler the chest. Move up the cups and collect all the cards!
Fight with friends or other players online
Online mode has the greatest replayability. It's on the highest level in Clash Royale. The game itself has become so popular largely thanks to the online mode and the clan system. Unite with friends in a separate clan in order to take part in championships and clashes of individual alliances. Build your team of champions and defeat all the enemies or challenge a friend to see which of you plays the best and who has the coolest deck.
Graphics and Sound
Clash Royale features modern 3D graphics with meticulously crafted, beautiful models and excellent detail. The project offers the user a picture with their own specific stylistics in character design. In addition, the game is rich in its own sound effects – each unit and each spell has its own peculiarity.
Mod Description
Clash Royale is free to play but comes with a lot of in-app purchases. We suggest you use a modified version of the game, where you can get access to a special private server with multiplayer mode, unlimited number of gems and coins, as well as with all the new maps unlocked. In addition, you will surely appreciate the generous loot from the chests, where you can pick epic cards. In general, you have almost unlimited opportunities for creativity.
Mod Testing
We have tested Clash Royale on our android devices. Based on the results, we can confirm that the mod works without failures and it is safe. Just download the modified version of the game and enjoy the fun experience on a private server.
Gameplay Tips
The gameplay consists of top-down arena battles that open as the game progresses. You can collect several decks for different tactics. At one point in time, there are only 4 cards at hand, and there are eight of them in the deck. These 4 cards are selected at random. Thus, the player never knows exactly when this or that character from the deck can become available.
Each player has three towers on the map. One is the main one – it stands a little further away and has more lives – and two minor ones protecting the main one. The player has a point displayed in the form of a crown for the destruction of each tower. If you destroy the main tower, the other two will break automatically. The battlefields have two parts, you can get to the enemy half along one of two paths – big battles unfold on these bridges. In short, the gameplay is very addictive.
Managing cards and decks is important element in Clash Royale, which takes a lot of the player's time. It is worth taking the time to think about which characters to improve, which abilities to update and what to add to a deck. General statistics are available in the game menu – top of the best players in the world. In addition, there is Royale TV – the ability to watch duels of other users. This helps to gain experience and build tactics for battles.
Our Summary
Clash Royale is an excellent strategy that doesn't require a lot of free time from the gamer, despite the fact that it is multiplayer. Dynamic battles with excellent graphics, animation and beautiful effects allow you to get real pleasure from the battle process. We also recommend you iconic Clash of Clans, as well as Coin Master.
How to install Clash Royale Mod?
We made everything to ease downloading process for every visitor of our website. However, if you download modded or hacked app from third party sources for a first time, the following how-to-do guide will be useful for you:
- Press download APK button and download process will start automatically.
- After its completion, open your file manager and select the necessary application file clash-royale-technifiser.com.apk.
- In case of installing APK file for the first time, your device may ask you several permissions. In order to allow installation process you have to open device settings and switch on "Allow from this source" tab.
- After the game installation completion, it becomes available for playing!
Don't forget to delete the original version of Clash Royale before installing our modified version to prevent errors during installation process.


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$46.00 $46.00
Richie House Girls' Pink Layered Dress with Rosette and Pearl Accents RH0918-A-7/8-FBA
White tiered skirt bottom charming braces long dress
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(pansy, pressed purple bougainvillea petals, dried peony petals, pine cone seeds, mussel shells, black beans)
Miniature, mailable, and frameable print with envelope. Reverse is blank, awaiting your own words. Print is 4.72 inches square. Envelope is 5 inches square. (square envelopes may require extra postage)
In the unlikely event that your prints do not arrive in perfect condition, please contact e-mail within two days.


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There are many different damaging insects and diseases that currently threaten New Hampshire's towns and forests. Most are not native to North America and spread quickly. Please use the resources provided to learn more and how you can help combat these invasions
Native Insects & Diseases
Native insects and diseases cause problems, too.


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- Cushioned temple tips provide non-slip comfort.
- Lightweight frame and suspended lens design provide perfect fit for a variety of users.
- Suspended lens provides stylish look, comfort fit, panoramic view and maximum protection.
- Scratch resistant polycarbonate lens provides 99% UVA/B/C protection.
- Adjustable nose piece provides 3 different angles, allowing the user to find the most comfortable fit. Ratcheting temples provide different angles for perfect view and fit.
- Passes MIL-PRF 32432 High Velocity Impact Standards.
General Specifications:
Bridge: 15mm
Lens Base: 8 Curve
Lens Size Diagonal: 141mm
Lens Size Vertical: 45mm
Lens Thickness: 2.2mm
Overall Length (Lens-Tip): 161mm
Overall Width (Hinge-Hinge): 128mm
PD: 68mm
Weight: 27gm
At Safety Station we do our screen printing in-house. Embroidery is also available! We offer competitive pricing and a quick turn around time.
Call us to get . . .


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Do More Than Vote…Help at the Polls
If you have wondered what you can do to help this election in addition to voting, we have an idea for you. What about volunteering at a polling location?
According the Massachusetts voter information guide…One of the best ways that you can help make sure Massachusetts holds successful elections this year is by offering your time to be a poll worker. Poll workers are needed across the Commonwealth on November 3, and many communities will also need workers to assist with early voting.
Poll workers are hired by local election officials to help check-in voters, distribute ballots, tally votes, and assist voters in the polling place.
This year, poll workers will also be needed to help sanitize booths and pens, direct voters, and monitor social distancing in the polling places. Having enough poll workers for every precinct is the best way to keep lines short and reduce crowding in polling places. Generally, poll workers must be registered voters of the Commonwealth, though up to 2 poll workers per precinct may be 16 or 17 years old. This year, if a city or town cannot find enough poll workers, they have the option of hiring workers regardless of their registration status or political party affiliation.
If you are able to offer your time to be a poll worker, please visit the Elections Division's website, www.sec.state.ma.us/ele, where you can find a listing of cities and towns in need of election workers. You do not need to be a resident of a city or town in order to be a poll worker there.


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Leftovers of Hurricane Ida ravage the Philadelphia area
Late yesterday evening, the Philadelphia area was subjected to brutal storms from the aftermath of Hurricane Ida, with the peak of the storm being arguably one of the worst in the area in a long time. There were tornados, vicious floods. It was like the apocalypse itself had come to the city.
I was in arguably one of the worst sections of last night's storm, the southern portion of Montgomery County. If you don't know, MontCo is just north of Philadelphia County. So instead of staying safe, I had to traverse through the floods and fire to referee a Division 3 volleyball game (I don't understand the rules of volleyball, but that's a story for another time).
While on the way there around 5:30 eastern, there were at least two tornadoes that touched down near me, one right where I was working and the other about 20 seconds from my home. Luckily, nobody I know of was hurt, but the aftereffects of the rain across Philadelphia were remarkable.
According to Montgomery County Incidents, I saw at most 116 emergencies going on simultaneously in my county. Some areas got it worse than here, with dozens of houses in Mullica Hill being ripped apart.
On my way back home later that evening, there were trees fallen everywhere, down wires, metal signs bent in half, at least a dozen fire trucks and ambulances. It was nothing like I'd ever seen before. The most confusing portion was passing seven empty cars in the middle of the road. There was no flooding or damage. The cars were just left there scattered.
Unfortunately, I didn't capture any of the scenes myself. I was too busy looting the abandoned vehicles on the side of the road.
Luckily, Facebook and Twitter were able to record last night's events. We have people fishing on the highway in Philadelphia, and I'm almost positive I saw a few canoes being taken out as well.
Former Philadelphia Eagles wideout Freddie Mitchell had to be saved from his home via boat after his house was submerged from the flood. After the fact Mitchell had to run to Walmart to get clothes in his underwear because all of his clothes were ruined in the flood.
I know so many are without power, and I hope everyone is back home and safe. Rumors have told me that Ben Simmons might've had something to do with this but can't guarantee that it was the case. My working theory is Rich Paul channeled his anger towards the Philly faithful through governmental weather control, but that information is a work in progress.
Last night's storms don't look to have any effect on Philadelphia sports. The Eagles are still practicing while the Phillies are on the road until next Thursday. Hurricane season is still upon us, so hopefully, no other storms will hit the east coast, and football season will continue as scheduled.
Mandatory Credit: Philly Voice