Experimental investigations of cathode-directed streamer propagation in air at high pressure

The experimental results of spatial-temporal and electrodynamical characteristics of cathode-directed streamer in air under different pressures are presented. The similarity laws, which allowed to compare the characteristics of discharge current and streamer dynamics under different pressures, were obtained. It was found that interval of pressures exists in which discharge develops similarly when the product P·d, and applied voltage are kept constant. It is important to note, that under these conditions average streamer velocity remains constant at different pressures