Spatiotemporal dynamics of a low-pressure arc and a generated beam in an electron source with a grid plasma emitter

The article presents results of studying the dynamics of a submillisecond low-pressure arc discharge in an electron source with a grid plasma emitter and a plasma anode, as well as the formation of an electron beam generated by it in a guiding magnetic field. Measurements of the currents to the electrodes of the plasma emitter discharge system and to additional probes installed in it demonstrated the spatial rearrangement of the discharge with subsequent achievement of a quasi-steady shape of the current density distribution on the emission electrode. Analysis of the current oscillograms at the end of the discharge current pulse made it possible to estimate the contribution of the electron emission current from the plasma emitter to the total current in the accelerating gap in the mode when the measured beam current is equal to or exceeds the discharge current. The factors responsible for reducing the spatial inhomogeneity of the beam current density are determined, and recommendations are given for improving its uniformity.