Ionization Processes in Arc Discharge of Low Pressure

Abstract

In this work, a model of the cathode spot of a vacuum arc in the framework of the drift-diffusion representation has been considered. The use of the drift-diffusion approximation eliminates the need to calculate the particle energy distribution functions and take into account various energy reactions that are not accompanied by a change in the particle charge. It has been shown that the field strength of the plasma column is significantly reduced. The column is surrounded by a space charge of slow positive ions, providing a high field strength in front of it. At the stage of the formed plasma boiler, the ionization of metal vapor occurs mainly in a thin layer in front of the ion cloud, and ion recombination prevails in the column.