Die Kopplungsmechanismen zwischen longitudinalen und transversalen Wellen in einem Plasma

Since electron plasma oscillations are assumed to cause nonthermal cosmical radiofrequency radiation, the problem of coupling between longitudinal and transversal plasma waves becomes important. Starting from the basic plasma equations all possible coupling mechanisms are deduced in a general way. Besides the hitherto known mechanisms as the effect of a pressure gradient, of an external magnetic field, and of a general flow or drift field, a new nonlinear “internal coupling“ effect which is able to generate electromagnetic radiation proves to be existent. Finally some remarks concerning the relativistic aspect of the problem are added, as errors are found in the literature.