Plasma opening switch characterization and optimization for inductive energy storage

Some experimental results on carbon plasma guns are reported. Plasma density, as a function of time, is measured both by microwave interferometry (37.5 GHz) and Faraday cups. Plasma velocity is measured by a time-of-flight technique with the Faraday cups and is, also, deduced from the axial resolution of the density measurement. The plasma composition is determined by time-integrated spectroscopy. The time evolution of line radiation has been correlated with both interferometry and charge collectors. Three different ion species have been observed and studied in time: H+, with velocity VH=7 cm/μs, and C+ and C2+, both with velocity VC=2 cm/μs. Both plasma expansion in space and electrode effects are studied by time-integrated photography.