Abstract
An experimental study has been made of the properties and characteristics of a glow discharge to a nearly spherical hollow cathode. Current densities in excess of 0.5 amp/cm2 can be drawn from the cathode with negligible deterioration from sputtering. In neon, the discharge exhibits a stable and reproducible negative volt‐ampere characteristic at currents of a few milliamperes. At these currents, probe measurements indicate the plasma in the hollow contains ∼1‐v electrons in concentrations greater than 1013/cm3.