Hollow cathode vacuum arc plasma electron source for the generation of a high-current DC electron beam

This article presents the principle of operation, design, and performance data of a hollow cathode vacuum arc plasma electron source. The required electric strength of the accelerating gap can be ensured by generating a longitudinal magnetic field in the electron extraction region. This method is used to generate a high current DC electron beam. The effect of the magnetic field on the discharge and the emission characteristics of the plasma electron source are observed. With extraction voltages up to 700 V, and a magnetic field as high as 100 mT, we demonstrate a DC emission current of roughly 9 A. The hollow cathode vacuum arc plasma electron source exhibits emission characteristics characterized by three different stages: a rapid increase stage in which high-energy electrons are extracted; a slow increase stage in which a small number of high-energy electrons and a large amount of low-energy electrons are extracted together; and a stable stage.