Analysis of the electron energy distribution, cross sections, and rate constants for electron collision processes in an oxygen plasma

The electron energy distribution has been measured in the positive column of an oxygen glow discharge over the pressure range 0.5--2.0 torr and over the current range 40--120 mA (the H form). The experimental results are analyzed; the electron ''sink'' and the effect of finite resistance of the plasma between the probe and the reference electrode are taken into account. The measured electron energy distributions are used to calculate the transport coefficients and rate constants for several reactions involving electrons which require a threshold energy. The results are compared with data found through numerical solution of the Boltzmann equation in several other papers. The intermediate-energy parts of all the calculated energy distributions agree with the measured distributions; the greatest differences are observed at high electron energies, because of the different cross sections used for the excitation of electronic states. Comparison of the calculations with experiment reveals a most probable set of cross sections and also reveals that several of the rate constants found in drifting electron clouds can be used for the conditions prevailing in a glow discharge