On the possibility of generation of runaway electron beams in red sprites

The paper presents experimental and theoretical investigations of the generation of runaway electron beams in laboratory analog of red sprites. Experiments show that during the formation of plasma diffuse jets initiated in the capacitive discharge plasma having no contact with metal electrodes, runaway electron beams generate at air pressure of 0.4 and 1 Torr. It is shown that during a single voltage pulse, two current pulses of runaway electrons are recorded on a collector with the sub-nanosecond time resolution. The capacitive discharge is simulated in a quartz tube of the inner diameter 5 cm at the pulse voltage up to 20 kV and ≈6 ns (≈3 ns pulse edge) half-height duration. It is found that strong electric fields can occur at a 1 Torr air pressure in the quartz tube, which is sufficient for the generation of runaway electrons.