[en] We consider time periodic em-pumps acting upon a stable plasma, so that all field quantities except the internal energy density are supposed to be periodic functions of time. Irreversible heating (or cooling) is represented by the time average of the rate of change of the internal energy density. (orig.)
Jun 1983; 55 p; With 41 refs., 12 figs. Invited review lecture given at 'The spring college on radiation in plasmas', 1983 of the International Centre for Theoretical Physics, Trieste (Italy).