Effect of gas pressure on amplitude and duration of electron beam current in a gas-filled diode

The parameters of an electron beam generated in helium in the pressure range $p$ = 10$^{-4}$–12 atm are studied. Nanosecond high-voltage pulses are applied to a gap between a tubular cathode and planar anode, which is made of 45-$\mu$m-thick AlBe foil. Behind the anode, an electron beam is detected at a helium pressure of 12 atm. The pressure dependence of the beam current amplitude shows three peaks at $p\approx$ 0.01, $\approx$ 0.07, and $\approx$ 3 atm. The beam-induced glow of a luminescent film placed behind the foil and the discharge glow at different helium pressures in the gas-filled diode are photographed.