Cumulation effect of an electron beam generated in a high-voltage nanosecond discharge plasma in vacuum and gas diodes

Abstract

Cumulation effect of a beam of runaway electrons formed in a high-voltage nanosecond discharge in air at pressures of 3-105 Pa and discharge gap length d of 1 - 5 mm was studied. Optimal conditions of the effect in discharge gap with a tubular potential cathode and grounded flat anode was achieved at an air pressure of ~ 5 Pa and d of 2.7 mm. An electron beam current pulse was recorded behind a foil anode with high (up to ~ 80 ps) time resolution. It was found that, due to the cumulation effect, a through hole is formed in an aluminum foil 20 μm thick after 2-3 discharge pulses. The electron beam was found to register around the zone of maximum beam current density as well. As follows