Effect of insulating films on the current of an electron beam from gas-filled diodes exposed to voltage pulses with a nanosecond rise time

Abstract

The parameters of subnanosecond electron beams generated in gas-filled diodes are studied. When the voltage pulse rise time is short (≈1 ns or less) and the electron beam is extracted from the diode through insulating films, the amplitude of the signal measured at the collector depends not on the electron beam current but on the electromagnetic radiation arising in the diode and the capacitive current from the collector. If the electron beam is extracted through thin metallic foils and fine metallic grids, the FWHM of the runaway electron pulsed beam is ≈0.1 ns and its amplitude reaches several hundreds of amperes.