Power balance and space-chargeconfinement in a neon dc column plasma

Abstract

The diffuse column of a dc glow discharge in neon is a typical exampleof a plasma whose properties are mainly determined by the non-local non-equilibrium kinetics of the electron component. Consequently,the space-charge confinement causes a spatial variation of all plasma properties.The effects on the power balance, the ionization budget and the radiation efficiency of a cylindrical column plasma are studied by a detailed self-consistent column model based on a hybrid method. The analysis deals with the impact of discharge parameter variations over larger ranges, of an admixture of a molecular gas as well as of thesuperposition of a longitudinal magnetic field on the spatial plasma structure.Among others, the non-local properties of the electron power balance and their influence on the radiation efficiency are discussed.The largest influence of energy transport processes on the electron power balancehas been observed in a range of the pressure times radius values from about 200 to 400 Pa cm, which nearly coincides with the range where the maximumefficiency of the resonance radiation occurs.