Self-oscillations of a positive corona in nitrogen

The oscillatory behaviour of a grow positive corona in pure nitrogen is observed experimentally. The regular self-oscillations of the corona current and the light emission from the glow ionization region, as well as the averaged volt-ampere characteristics of this discharge, are studied comprehensively within gas pressure range 10-765 Ton. It is revealed that the positive glow corona generates a soft x-radiation. This radiation plays a crucial role in the photo-ionization of nitrogen. Furthermore, it provides a fast positive feedback for electron avalanches through the ionization region of the corona. The results of numerical modelling of the glow corona under free-running oscillations are also presented.