Operation Features of a Nonself-Sustained Glow Discharge in a Tube Initiated by a Focused Electron Beam in the Forevacuum Pressure Range

We report our investigations on the current distribution of a nonself-sustained glow discharge along a long, narrow metal tube when a focused electron beam generated by a forevacuum plasma-cathode gun is injected into this tube. It is shown that the injection of accelerated electrons affects the current distribution along the length of the tube. The minimal beam current that ensures a uniform discharge distribution in the tube decreases with increasing tube diameter, increasing operating gas pressure, and decreasing accelerating voltage.