Effect of self-consistent electric field on the rate of solid evaporation in a hot plasma

A problem on particle entering the plasma from the solid surface is of interest in connection with analysis of the rate of macroparticle evaporation in tokamak plasma, as well as in connection with astrophysical problems. Potential difference between the solid surface and hot plasma, when the rate of solid evaporation is sufficiently high, and electron countercurrent flow from the cold plasma is sufficient for compensation of hot electron flow, is considered. It is shown that the potential difference between hot and cold plasma remains to be considerable, ∼2Te/e. Ion sound instability, which leads to appearance of anomalous resistance and electron cloud heating, is driving in the external part of the cold plasma cloud, where the current rate of cold electrons exceeds the rate of ionic sound. The concentration profile of with drawing cold plasma in this case changes its state, and on the boundary between cold and hot plasma a moving binary layer is formed