Nonlinear resonant interaction of three extra-ordinary waves in a hot electron plasma

The coupled mode equations and coupling coefficients for the resonant nonlinear interaction of three extra-ordinary waves in a hot magnetized plasma are derived by Whitham's method of averaged Lagrangian. The wave vectors of the three waves are taken as noncollinear and perpendicular to the external uniform magnetic field. Of the three waves one is of high frequency mode and the other two are of low frequency mode. (author)