Generation of runaway electrons and X-ray at a microsecond voltage rise time
The results of studies of the generation of runaway electron beams and X-ray radiation in an inhomogeneous electric field at pressures of air, nitrogen, argon and helium ranged from 1 to 100 kPa are presented. A pulser generating voltage rise time of ~ 1.5 μs and an amplitude of up to 200 kV was used. X-ray radiation was detected by a scintillator and a PMT behind an aluminum foil anode in the total pressure range in all four gases. In helium, a runaway electron beam at a pressure of 100 kPa was recorded by a collector. In air, nitrogen, and argon, a runaway electron beam had relatively small amplitudes and energies, and was recorded by the collector only at low pressures (< 20 kPa). For a microsecond voltage rise time, it is necessary to use cathodes providing the highest gap breakdown voltages.