Runaway electrons preionized diffuse discharges at high pressure

The paper presents the results of experimental research on nanosecond high-pressure diffuse discharges in an inhomogeneous electric field with a time resolution of ~100 ps. It is shown that decreasing the voltage pulse duration enhances the feasibility of diffuse discharge with no additional ionization. In particular with a narrow interelectrode gap, a diffuse discharge in atmospheric pressure air with preionization by runaway electrons or shortly a runaway-electron-preionized (REP) diffuse discharge (DD) was realized. It is found that most of the energy is deposited to the REP DD plasma once the voltage across the gap reaches its maximum.