Half-open Penning trap with efficient light collection for precision   laser spectroscopy of highly charged ions
  We have conceived, built and operated a 'half-open' cylindrical Penning trap for the confinement and laser spectroscopy of highly charged ions. This trap allows fluorescence detection employing a solid angle which is about one order of magnitude larger than in conventional cylindrical Penning traps. At the same time, the desired electrostatic and magnetostatic properties of a closed-endcap cylindrical Penning trap are preserved in this congfiuration. We give a detailed account on the design and confinement properties, a characterization of the trap and show first results of light collection with in-trap produced highly charged ions. 
David von Lindenfels, Manuel Vogel, Wolfgang Quint, Gerhard Birkl,   Marco Wiesel
physics.atom-ph