Increasing the Pulse Energy of a Radially Converging Low-Energy High-Current Electron Beam

The energy characteristics of a high-current electron gun with a radially converging beam have been studied. The cathode unit of the gun consisted of one or two ring sections with an inner diameter of 8 cm, each of which included 18 resistively decoupled arc plasma sources initiated by discharges over the dielectric surface. It is shown that electrostatic shielding that prevents the liberation of electrons and ultraviolet radiation from cathode and anode plasmas to the space behind the cathode decreases the probability of the breakdown development along the resistors of arc plasma sources and increases the beam pulse energy released in the anode approximately two times. In the case of two-sectioned cathode unit, the width of the beam autograph on the anode (melting trace) was ~7 cm at an axial distance between the centers of the sections of 4 cm.