Theoretical and experimental study of the influence of nitrogen admixture on characteristics of dc diffuse glow discharge in rare gases at intermediate pressures

Abstract

An effect of nitrogen admixture on the electric field in positive column of diffuse glow discharge in various rare gases at intermediate pressures is studied both experimentally and theoretically. The discharge is maintained in a cylindrical glass tube. Earlier it was observed and reproduced in calculations that addition of N2 (1%) to Ar at pressure 40 Torr led to noticeable decrease in the electric field strength at a fixed discharge current. In the present work there are results for pure Ne and Ne + 1%N2 gas mixtures at pressure 40 Torr. It is found that the addition of N2 to Ne leads to the increase in the electric field strength; the observed effect is reproduced in calculations. The explanation of differences in the impact of N2 addition on the electric field strength in Ar and Ne discharges is given. On the basis of the performed analysis it is predicted that the addition of N2 to He leads to the increase in the electric field in the discharge and the addition of N2 to Xe leads to the decrease in the electric field. For the case of He, the prediction is experimentally confirmed in this work, while for the case of Xe, it is corroborated by literature data.