Effect of toroidicity during lower-hybrid mode conversion

The effect of toroidicity during lower-hybrid mode conversion is examined by treating the wave propagation in an inhomogeneous medium as an eigenvalue problem for ω2(m,n), m, n poloidal and toroidal wavenumbers. It is possible that excitation of toroidal modes rather than geometric optics may determine the wave coupling to the plasma. The level of density fluctuations in tokamaks, may cause enough k sub(parallel to) scattering to mask the toroidicity effects. It is shown that a wide k sub(parallel to) spectrum excited by a monochromatic pump will persist even with vanishing fluctuation level. (author)