Metastable atom density in helium, neon, and argon glow discharges

Abstract
A theoretical model of the positive column of a rare gas glow discharge is used to calculate metastable atom densities in the pressure x radius range from 0.01 to 1.0 Torr cm. Two body quenching is shown to be an important loss process for metastables in neon and argon discharges above 0.1 Torr cm. Measurements of metastable atom flux from an anode slit are reported for the title gases and shown to represent the metastable density in the anode fall region of the discharges.