The ionization waves propagation in a long capillary dielectric tube in the absence of surface charge

Abstract

Abstract The initiation of the electrical breakdown in a narrow tube filled with a gas under reduced pressure requires the voltage higher compared to that for a much broader tube. Besides, at the fixed applied voltage formally sufficient for breakdown, the probability for the breakdown happening in a narrow tube is far from 100%. This probability can be increased appreciably if to organize the surface ionization waves preceding the volume breakdown in a narrow tube. The breakdown development in a long capillary dielectric tube induced by the surface ionization waves was investigated in this work. The experiments were carried out with the use of a quartz capillary tube with a high aspect ratio of length to diameter. The tube was filled with helium at pressures of 1 - 30 Torr. The pre-posited surface charge on the tube wall was absent. It has been found the completed high-current breakdown between two electrodes located at the ends of the long capillary tube develops with a high probability with the presence of surface ionization waves within the tube.