Nonlocal phenomena in the positive column of a glow discharge in molecular gases

The influence of nonlocality of the electron energy distribution function on the parameters of a positive column of a molecular gas discharge at a mean pressure from the range 1 ≤ pR ≤ 10 cm Torr is studied. Under these conditions, the electron energy relaxation length is small compared with the characteristic size of the plasma region; that is, calculation can be carried out in the local approximation. For fast electrons at the periphery of the discharge, where the ambipolar field exceeds the longitudinal one, the local approximation may introduce significant errors into the basic parameters of the positive column. The nonlocality of the electron energy distribution function is found to increase excitation constants from the center of the discharge to its periphery.