Propagation of streamer channel in gap with large gas pressure difference

A theoretical study of the electrical breakdown pattern of a gas-discharge gap under a large (10-fold) gas pressure difference is presented. This discharge simulates the luminous structures in the Earth’s upper atmosphere, such as red sprites. The main differences between a discharge under the pressure gradient conditions and a discharge in a homogeneous gas medium are identified. It is shown that the spatial transition of the discharge from a diffuse column to a branching streamer is caused by a localized pressure decrease and an excessively reduced electric field strength above a threshold value, approximately equal to the static breakdown strength.