Radiative and other effects from internal waves in solar and stellar interiors.

Starting from the usual spherical mode and planar Boussinesq formulations, equations are derived for the propagation and dissipation of internal gravity waves in a stellar interior. The sun is 'transparent' to such waves if they have sufficiently low mode number (less than 10) and high frequency (more than 10 times the convective overturn frequency). Even when spatially and temporally incoherent, such waves focus toward the center of the sun, so that their amplitude greatly increases there. An order of magnitude estimate suggests that the internal waves generated at the base of the convective zone may become nonlinear in amplitude close to the solar center. If this happens, several effects become important and can affect, e.g., the expected Cl-37 solar neutrino signature. Possible effects include (1) hydraulically enhanced diffusion of entropy, which can increase the effective radiative opacity of the solar material by a factor of order unity, and (2) wave-induced turbulence, which can lead to species mixing.