Mathematical Model of Current Distribution in a Tungsten Plate during Pulsed Heating

In this paper, for the first time, we present a new model of current distribution in atungsten sample and of substance evaporation when the surface is heated by an electron beam.The model is based on solving electrodynamics equations in a cylindrical coordinate system usinga model temperature distribution in the sample and a thin layer of evaporated tungsten. Themodel is analyzed in a simplified formulation at constant values of electrical resistance andthermoelectric power in gas and metal. The dependence of the amplitude and isolines of thermalcurrents on the distribution of temperature at the sample surface is shown. The model parametersare taken from experiments at the Beam of Electrons for materials Test Applications (BETA)facility, created at the Budker Institute of Nuclear Physics of the Siberian Branch of the RussianAcademy of Sciences.