Parametric instability of MHD waves in a refraction plasma waveguide with an exponential density profile and an oblique magnetic field

Non-linear resonance interaction of low-frequency magneto-acoustic waves in a refraction plasma waveguide with exponential density profile and bent magnetic field is considered. Waveguide normal modes are found; resonance conditions are revealed; simplified equations for complex amplitude waves are derived. Parameters of the induced LF oscillations are analysed in the intense pumping approximation. 10 refs., 6 figs., 2 tabs