Plasma‐cathode electron gun

The plasma‐cathode electron gun is a new type of electron source which is suitable for applications requiring a large area, high‐energy electron beam. It employs a plasma generated within a cold low‐voltage, hollow‐cathode discharge as the source of electrons. Plasma cathode devices are characterized by their simplicity and versatility, and they offer a number of advantages over other designs. An electron gun producing a beam with dimensions of 5×125 cm has been developed for use with high‐power cw gas lasers. This device has been operated at beam energies of 150 keV and cw beam current densities of 0.1–0.2 mA/cm2.