A study of the high current discharge of the pseudospark and back lighted thyratron switch

Summary form only given. An experimental and theoretical study of the high-current discharge of the pseudospark and back-lighted thyratron switch was performed. These are hollow-electrode low-pressure gas discharge switches that have been operated at voltages up to 100 kV and currents up to 100 kA. They are also a source of electron and ion beams and produce microwave radiation through a beam-plasma interaction. Streak camera observations and electrical measurements have identified two phases of the discharge: a high-impedance formation phase which draws current from a hollow cathode and a low-impedance conduction phase which draws currents from the front surface of the cathode which has been heated during the formation phase by ion bombardment. During the formation phase, ion beams, electron beams and microwaves are produced. During the conduction phase, current densities of ~10 kA/cm² are conducted through a homogeneous plasma with a large cross-sectional area. Theoretical modeling indicates that a beam component of electrons can contribute to the formation of the discharge and the conduction of high current densities