Formation of ball streamers at a subnanosecond breakdown of gases at a high pressure in a nonuniform electric field

• Published in: JETP letters 2017-11, Vol.106 (10), p.653-658
• Main Authors: Beloplotov, D. V., Tarasenko, V. F., Sorokin, D. A., Lomaev, M. I.
• Format: Article
• Language: English
• Subjects: Atomic; Biological and Medical Physics; Biophysics; Breakdown; Electrodes; Electron avalanche; Electron beams; Foils; Helium; Hydro- and Gas Dynamics; Molecular; Neon; Optical and Plasma Physics; Particle and Nuclear Physics; Physics; Physics and Astronomy; Plasma; Quantum Information Technology; Solid State Physics; Spintronics; Streak cameras; Streamer formation; Voltage pulses
• ISSN: 0021-3640; 1090-6487
• DOI: 10.1134/S0021364017220064

The formation of a diffuse discharge plasma at a subnanosecond breakdown of a “cone–plane” gap filled with air, nitrogen, methane, hydrogen, argon, neon, and helium at various pressures has been studied. Nanosecond negative and positive voltage pulses have been applied to the conical electrode. The experimental data on the dynamics of plasma glow at the stage of formation and propagation of a streamer have been obtained with intensified charge-coupled device and streak cameras. It has been found that the formation of ball streamers is observed in all gases and at both polarities. A supershort avalanche electron beam has been detected behind the flat foil electrode in a wide range of pressures in the case of a negatively charged conical electrode. A mechanism of the formation of streamers at breakdown of various gases at high overvoltages has been discussed.