Supershort avalanche electron beam generation in N2 and He at quasi-continuous gap voltage

Generation of a supershort avalanche e-beam (SAEB) in nitrogen and helium at quasi-continuous gap voltage has been shown. SAEB duration at generator voltage of 25 kV is ∼200 ps at a half-height, and its delay time with respect to the voltage pulse risetime may be tens of nanoseconds. The beam current waveforms, having several subnanosecond peaks have been recorded. It was established that at SAEB generation the gap voltage is decreasing by 10–20%. The change in oscillating mode of beam current of fast electrons in a gas-filled diode at He and N2 pressure decay was registered. Duration of the beam current of the fast electrons in an impulse increased up to several nanoseconds, and the impulse had two peaks on the osciloscope trace.