Pressure and electron energy measurements in a channel spark discharge

We present the results for a channel spark discharge which show a substantial difference between the pressure in the experimental chamber and the pressure in the hollow cathode (HC). For the pressure range (1-8) x 10(-2) Torr measured in the experimental chamber, the pressure in the hollow cathode is changed in the range (8-16) x 10(-2) Torr. An analysis of the pressure data obtained by pumping of the experimental chamber via the HC showed that there are three modes of the system pumping, namely molecular, transient and viscous. Finally, it was shown that applying a discharge voltage with amplitude up to 50 keV allows electron beams to be generated with an efficiency up to 10%, a maximum electron energy spectrum at about 25 keV and a current amplitude of several hundred amperes.