Electron temperature relaxation rates in flowing afterglow plasmas containing molecular nitrogen and oxygen

Measurements have been made, at gas temperatures of 300K of electron temperature, T e , relaxation rates (2000K>or approximately=T e >or approximately=350K) in pulsed flowing afterglow plasmas of pure argon and argon-nitrogen and argon-oxygen mixtures. Momentum transfer cross sections were derived, which are in good agreement with previous data. Values of G, the fraction of energy transferred per collision, were deduced using previously published results for momentum transfer cross sections. These G values show a marked variation with T e as expected and are interpreted in terms of energy transfer to rotational states of the molecules. The G values over the complete T e range are less than theoretically predicted in the case of nitrogen, but greater than predicted in the case of oxygen.