Temporal and spatial evolutions of gas discharge induced by a high-power, pulse microwave

Summary form only given. High-power, short-pulse microwave with the peak power of 20 MW, frequency of 13 GHz and pulse duration of 14 ns, which is generated from a virtual cathode oscillator, is irradiated on a gap space between a spherical and a spherical electrodes to induce gas discharge. The electrode is being biased at a constant dc voltage less than that for breakdown at the moment of microwave pulse injection. The gap separation is 15 mm. Gas pressure is changed from 760 Torr to 50 Torr. A high-speed image converter camera observes temporal and spatial evolutions of gas discharge luminescence.