Switching of 100-kV pulses in a planar “open” discharge with generation of counterpropagating electron beams

Some results of studying a planar “open” discharge with generation of counterpropagating electron beams at high voltages and appreciable working gas pressures up to atmospheric one are presented. The possibility of its functioning in helium at a voltage above 100 kV is demonstrated, and an increase in the working voltage does not prevent fast breakdown with characteristic switching times of $\sim$1 ns. A specific feature of this type of discharge is the existence of a gas-pressure region, where the discharge-development delay time nonmonotonically depends on the voltage due to the competition between emission processes leading to breakdown.