Abstract: The diffuse and corona discharges are used in different fields, including for modification of surfaces, pumping lasers and exciting excilamps. The report provides a short review of our research data showing the role of runaway electrons (REs) in formation diffuse and corona discharges in an inhomogeneous electric field at high pressures. The generation of runaway electron beams in high-pressure gases is a fundamental physical phenomenon that began to be investigated in the last century. Due to REs, diffuse discharges are formed in various gases without a source of additional preionization. The review is supplemented with respective diagrams and with images captured at high resolution to trace the plasma dynamics of nanosecond gas discharges from early prebreakdown stages until their final diffuse appearance. To obtain runaway beams that can be recorded at atmospheric pressure and more behind the anode foil, cathodes with a small radius of curvature and voltage pulses with an amplitude of about 100 kV and higher with a subnanosecond rise time are usually used. From the data presented can grasp the idea of how such discharges develop at negative and at positive voltage polarity, what setups and conditions are best suited to detect runaway electron beams, and what factors influence their amplitude, duration, and energy. Also analyzed are the streamer mechanisms of diffuse discharges and the generation of runaway electrons in high-pressure gases in an inhomogeneous electric field. In addition, data on cleaning and oxidation of various surfaces using diffuse discharges will be presented.

Keywords: Diffuse discharge, corona discharge, runaway electrons, application for modification

Biography: Victor F. Tarasenko was received the Ph.D. in 1976, the D.Sc. in 1988, and the Professor in 1994. Currently, he is a Chief Researcher of Optical Radiation Laboratory Institute of High Current Electronics SB RAS and the Professor of Tomsk State University and Tomsk Polytechnic University, Russia. V.F. Tarasenko co-authored more than 900 publications, 70 inventions, 23 reviews, 11 monographs, and 3 textbooks for students. He is a member of the Editor board of journals “Laser and Particle Beams”, “Atmospheric and Oceanic Optics”, “Quantum Electronics” and “High Voltage”. His research interests are in physics of gas discharges and generation of runaway electrons, spontaneous UV and VUV sources (excilamps) and their application, dense-gas pulsed lasers.