Production and Diagnostic Measurements of Kilovolt High-Density Deuterium, Helium, and Neon Plasmas

Abstract

This paper reports successful production and diagnostic measurements of kilovolt high-density plasmas of deuterium, deuterium-helium mixtures, helium, and neon. Particular attention was given to obtaining a systematic understanding of the electron and ion heating and cooling processes, as well as the attendant equilibration processes. These plasmas typically psosessed 1<Te<10 keV, 2×1019 <ne<1020 cm−3, 2×1018 <ni<1020 cm−3, copper contamination levels of nCu∼5×1017 cm−3, energy densities ∼105 J/cm3, and effective lifetimes ∼0.5 μsec. Diagnostic measurements were made with absolute time-resolved x-ray and neutron detectors, magnetic and electric probes, and high-speed visible photography. The plasmas were generated in a coaxial discharge tube, with the ions being heated primarily through collapse of the quasicylindrical current sheet, in a manner reminiscent of the linear pinch effect. The electrons rapidly achieved kilovolt temperatures via collisions with the energetic ions; radiation cooling of the electrons was observed, late in time, particularly for those plasmas consisting of high-Z ions.