PARAMETRIC-INSTABILITY OF MHD WAVES IN A REFRACTIVE PLASMA WAVE-GUIDEWITH AN EPSTEIN DENSITY PROFILE AND AN OBLIQUE MAGNETIC-FIELD

The nonlinear resonance interaction of low-frequency magnetosonic wave s is studied in a refractive plasma waveguide with an Epstein density profile and an oblique magnetic field at an arbitrary angle to the gui ding surface. In the MHD approximation, the conditions for the propaga tion of waveguide eigenmodes are found, the parametric excitation of m agnetosonic triplets is discussed, and the effects of both plasma dens ity stratification and orientation of the external magnetic field on t he nonlinear mode interaction are investigated.