Influence of electromagnetic radiation on the shock structure formation incomplex plasmas

Electromagnetic radiation effects are calculated for the case of the solar radiation spectrum in the vicinity of the Earth. The influence of the photo electric effect on the propagation of nonlinear waves in complex plasmas is studied when the dust grains acquire large positive charges. Exact solutio ns to nonlinear equations in the form of steady-state shocks that do not in volve electron-ion collisions are found, and the conditions for their exist ence are obtained. In contrast to the classical collisionless shock waves, the dissipation due to the dust charging involves the interaction of the el ectrons and ions with the dust grains in the form of microscopic grain curr ents and the photoelectric current. The nonsteady problem of the evolution of a perturbation and its transformation into a nonlinear wave structure is considered. The evolution of an intense, initially nonmoving region with a constant increased ion density is investigated. It is shown that the evolu tion of a rather intense nonmoving region with a constant increased ion den sity can result in the formation of a shock wave. In addition to the compre ssional wave, a rarefaction region (dilatation wave) appears. The presence of a dilatation wave finally leads to the destruction of the shock structur e. The possibility is discussed of the observation of shock waves related t o dust charging in the presence of electromagnetic radiation in active rock et experiments, which involve the release of a gaseous substance in the Ear th's ionosphere in the form of a high-speed plasma jet at altitudes of 500- 600 km. (C) 2001 MAIK "Nauka/Interperiodica".