On the mechanism of picosecond electron beam generation in gas-filled diode with cold cathode

The formation of a picosecond beam of runaway electrons in a gas-filled acceleration gap with a cold cathode and a strongly nonuniform electric field was investigated. The duration and amplitude of the current pulse of the picosecond runaway electron beam behind the anode foil were measured. The emission region of the beam in a gas-filled diode was specified experimentally. The time-of-flight method was used to investigate the conditions of particle acceleration in the gap. It has been demonstrated that the point within the rise time of the accelerating voltage pulse at which the beam is injected into the gap correlates with the magnitude of the macroscopic electric field at the cathode emitting edge.