A long‐pulse 300 keV electron gun with a plasma cathode for high‐pressure gas lasers

The design and main features of a plasma cathode electron gun for high‐pressure gas lasers are discussed. The mesh plasma cathode in combination with a low‐pressure gas discharge was used for the formation of a large cross‐section (55×4 cm2) electron beam with emission current densities up to 1.7 A/cm2, accelerating voltages up to 300 kV, and a pulse length of 20 μs (full width at half maximum).