Numerical study of the generation of runaway electrons in a gas diode with a hot channel

Abstract

A new method for increasing the efficiency of runaway electron beam generation in atmospheric pressure gas media has been suggested and theoretically proved. The method consists of creating a hot region (e.g., a spark channel or a laser plume) with a decreased numerical density of gas molecules (N) near the cathode. In this method, the ratio E/N (E—electric field strength) is increased by decreasing N instead of increasing E, as has been done in the past. The numerical model that is used allows the simultaneous calculation of the formation of a subnanosecond gas discharge and the generation of runaway electrons in gas media. The calculations have demonstrated the possibility of obtaining current pulses of runaway electrons with amplitudes of hundred of amperes and durations of more than 100 ps. The influence of the hot channel geometry on the parameters of the generated beam has been investigated.

Runaway electrons in diffuse gas discharges

“…The generation of anode-reaching runaway electron beams in laboratory discharges and beams which pass through anode foils has been studied on different models and in different approximations [27,29,35,[89][90][91][116][117][118][119][120][121][122][123][124][125][126][127][128][129][130][131][132][133], and the results have revealed a series of tendencies in common with what is observed in experiments. Data are also available on the criterion of electron runaway and on the mechanism of processes involved in runaway electron generation.…”

Investigation of the switching characteristics of high-pressure subnanosecond gas dischargers with the purpose of a sharp increasing of the breakdown voltages and the switching speed

“…The dynamics of the electromagnetic field in a gas diode was calculated using the Maxwell equations system. Earlier, using a similar technique, a number of problems were solved for modeling the dynamics of the development of subnanosecond discharges developing with the participation of RAEs [87,91,92]. The modeling performed showed that the velocity of the IW motion sharply increases when moving through the gas ionized by RAEs.…”

Влияние Скорости Волны Ионизации На Напряжение В Линии При Развитии Импульсного Пробоя

“…Начальная стадия развития импульсного пробоя перенапряженного промежутка с сильно неоднородным электрическим полем сопровождается формированием пучка убегающих электронов [1][2][3][4][5][6][7][8][9][10]. За этим пучком следует волна ионизации, которая представляет собой резкий градиент концентрации заряженных частиц в направлении ее движения.…”