Filamentation instability in magneto plasmas

Abstract
It is shown that the filamentation of ordinary-mode pumps propagating at an arbitrary angle with respect to the magnetic field has to be magnetic field-aligned, but not for extraordinary-mode pumps. A general dispersion relation is derived including the effects of magnetic field and collisions, and the nonlinear effects of ponderomotive force, thermal focusing force, and the beating currents. Threshold field and growth rates are obtained and compared to the results of the unmagnetized and collisionless case. Applications of these results to ionospheric modifications are discussed.