A novel cold cathode sheet-beam plasma cathode electron gun and its beam diagnostics

Summary form only given. In this work a novel cold cathode sheet-beam plasma cathode electron (SPCE) gun has been reported. The discharge in the SPCE-Gun is an axially symmetric, self-sustained, transient, low pressure gas discharge. In a hollow cathode cavity the plasma is a profuse source of electrons, which has been used to generate the sheet electron beam from the rectangular aperture of dimensions 7 mm × 1 mm. The whole assembly of SPCE-Gun consists of trigger unit, discharge unit and hollow cathode-anode assemblies along with drift space region. An intense beam current density ~1 kA/cm² through the pseudospark discharge of argon plasma has been achieved from this gun for pulse duration of ~200 nsec in a single shot experiment.To diagnose the generated beam, an arrangement of three isolated metallic sheets has been proposed. Also the actual shape and size of the sheet electron beam have been obtained through a non-conventional method by proposing a dielectric charging technique and SEM based image analysis. As distinct from the earlier developed sheet beam sources, the generated sheet-beam has been propagated more than 190 mm distance in the drift space region maintaining its sheet structure without assistance of any external magnetic field. The deviation from its original size of 7 mm X 1 mm is experimentally found less than ~23% along the longer side while along the shorter side it is even less than ~20%. The delayed voltage breakdown together with a fast current rise in this SPCE-Gun resulted in a class of highly intense sheet electron beam generation useful for many pulsed-power applications. Results of these efforts will be presented.