Temperature dependence of thermal accomodation of helium on tungsten surface, covered with adsorbate

The dependence has been obtained for the coefficient of energy accomodation of helium molecules on tungsten on the temperature of the surface and the degree of its filing by adsorbed impurities. A qualitative interpretation of the experimental results is given on the base of a quntum kinetical approach to the description of the molecules scattering by the solid surface in the presence of the adsorbate