Influence of quartz tube on the nanosecond pulsed discharge in a cone-to-plane air gap

This letter reports on the experimental investigation of the influence of a quartz tube on the nanosecond pulsed discharge in a cone-to-plane air gap, with the quartz tube inserted between the electrodes in the direction parallel to the electric field. While the tube is moved along the axies of the electric field, four different phenomena appear, of which the possible mechanism is discussed. The characteristics of the discharges are diagnosed by optical methods. For five conditions, the rotational temperatures are all 295 K, and the vibration temperatures are all 2200 K, the results mentioned above demonstrate that the plasmas generated in different conditions are in a nonequilibrium state each. Furthermore, a way to produce raise to a uniform glow-like discharge mode is proposed.