ELECTRON-BEAM GENERATION DURING THE HOLLOW-CATHODE PHASE OF PSEUDOSPARK DISCHARGES

From calculations using a two-dimensional, hybrid fluid-particle model , the mechanism for the production of the high-current electron beam o bserved during the hollow cathode phase of pseudospark discharges is i dentified. The predicted beam properties are in good qualitative agree ment with experiments; the onset of the beam current is abrupt and the current in the beam is some 10%-30% of the discharge current. Two dis tinct components appear in the energy spectrum of the beam. A sizable fraction of the current is carried by electrons with an energy corresp onding to the voltage applied to the discharge. A distinct low-energy beam is also predicted with a spread in energy of several 100s of eV