Features of the electron avalanche formation process in a strongly inhomogeneous electric field under high overvoltages

The simulation of the electron avalanche formation process in subnanosecond discharges of high pressure was carried out by means of the Monte-Carlo approach. The discharge gap under consideration was of the configuration “the finger-shaped cathode – the hemispherical anode”. The presence of a conic-shaped microprotrusion on a cathode surface was assumed. Such the electrode configuration provided the strongly inhomogeneous distribution of an electric field. A gas simulated was nitrogen at a pressure of 6 atm. An average electric field strength across the discharge gap was varied from 200 kV/cm up to 400 kV/cm. Microprotrusion height was varied from 0 um up to 30 um. The critical size and formation time of an electron avalanche were determined under various conditions simulated. The threshold electric field strength for electrons to transit into the continuous accelerating regime was calculated for various heights of the microprotrusion. The applicability of the non-self-consistent Monte-Carlo technique for the investigation of the runaway electron kinetics and the correct simulation of the runaway electron beam transport across the discharge gap was shown.

Spatiotemporal Characteristics of Radio Frequency Dielectric Barrier Glow Discharge at Atmospheric Pressure

In this paper, argon was used in radio frequency (13.56 MHz) dielectric barrier discharge (rf-DBD) at atmospheric pressure. The IV curve was recorded after gas breakdown, and discharge photos were captured by ICCD camera. Discharges of α mode and γ mode were observed based on IV curve and ICCD photos. As the existence of negative glow in γ mode, the luminescence intensity of different position of the discharge gap was analyzed. It was found that in the α mode, the electron avalanche occurs from negative to positive and negative glow appeared after the discharge changed into γ mode. In every half cycle, the peak position of negative glow is 13 ± 1 ns later than that of electron avalanche on cathode surface.

Electromagnetic Fields due to an Electron Avalanche

<p>The present work has been able to relate the magnetic field produced to the basic physical ionization process and derive a general expression for the same starting from the fundamental retarded scalar and vector potentials (Leinard-Weichert potentials). <b></b></p>

Electromagnetic Fields due to an Electron Avalanche

<p>The present work has been able to relate the magnetic field produced to the basic physical ionization process and derive a general expression for the same starting from the fundamental retarded scalar and vector potentials (Leinard-Weichert potentials). <b></b></p>

Catalog of TGEs observed at Aragats during 2008-2020

&lt;p&gt;For 12 years we monitored particle fluxes on Mt. Aragats 7/24 and discovered the most&lt;br&gt;powerful natural electron accelerator operated in the thunderclouds. This natural electron&lt;br&gt;accelerator provided more than 450 Thunderstorm Ground enhancement events (TGEs). We&lt;br&gt;make exhausting analysis of these events and will present yearly and monthly distributions,&lt;br&gt;as well the day hour distributions. Also, we will present the distribution of the outside&lt;br&gt;temperature and precipitation occurrences which are correlated with particle fluxes. We&lt;br&gt;address questions about TGE evolution and atmospheric conditions supporting the&lt;br&gt;origination of the relativistic runaway electron avalanches and demonstrate the relativistic&lt;br&gt;runaway electron avalanche is possible on Aragats only in Spring-Autumn seasons.&lt;/p&gt;