Study of a helium laser pumped by a pulsed electron beam generated in an open discharge

A laser on the self-contained helium 2¹P₁⁰ — 2¹S₀ transition pumped by a pulsed electron beam generated in an open discharge is simulated and experimentally studied. Lasing without decreasing the pulse energy in a tube of diameter 31 mm was observed up to the pump pulse repetition rate of 10 kHz determined by the parameters of a power supply. Dynamics of the electric field in an accelerating gap and populations of the working levels of helium are calculated. The radiation power calculated in accordance with its radial distribution measured in the saturated amplification regime is 7.85 times higher than that in the lasing regime. The practical laser efficiency of 0.056% is achieved for the quantum efficiency of 0.7%.