Interaction of impurity ions with a weakly non-Maxwellian simple hydrogenic plasma

The average acceleration of an ensemble of ‘‘test particles’’ in a plasma is called the ‘‘dynamical friction’’; the average rate at which their velocity vectors spread out in velocity space is expressed in a velocity-space diffusion-rate tensor. These quantities have been derived for impurity ions interacting with a weakly non-Maxwellian simple hydrogenic plasma. The derivation is sketched briefly in this Brief Communication; for details, the reader is referred to a supplementary report (see NTIS Document No. DE88017137).