Coupling: Summary Report

Abstract

W. R. Larenz' review paper (printed in this issue) presented a systematic categorization of various linear and nonlinear coupling mechanisms encountered in the hydrodynamically approximated warm plasma. As on several occasions during this symposium, the range of validity of the fluid model was questioned; the discussion provided the usual answers of the adequacy of the model as long as the wave numbers of electron or ion waves involved in plasma processes are well below the Debye wave number kD. The utility of the fluid model, when adequate, was emphasized in connection with radiation and boundary value problems since the complexities introduced by kinetic theory tend to render much of the required analysis intractable. For better understanding of the influence of anisotropy, it was pointed out that substantial anisotropy in the particle velocity distribution may be accommodated by an anisotropic pressure tensor within the hydrodynamic description.