Negative corona in nitrogen-oxygen mixtures

Current pulse shapes have been measured in negative point-to-plane corona discharges in oxygen, nitrogen-oxygen and argon-oxygen mixtures, with particular reference to the plateau on the trailing edge of the pulses. It was found that argon behaves as a passive third body in argon-oxygen mixtures, while nitrogen plays an active role in the physical processes which determine the current pulse shape and size. The implications of these results on theories of current pulse formation are discussed.