Effects of large-scale convection on p-mode frequencies

We describe an approach for finding the eigenfrequencies of solar acoustic modes (p-modes) in a convective envelope in the Wentzel-Kramers-Brillouin l imit. This approximation restricts us to examining the effects of fluid mot ions that are large compared with the mode wavelength but allows us to trea t the three-dimensional mode as a localized ray. The method of adiabatic sw itching is then used to investigate the frequency shifts resulting from sim ple perturbations to a polytropic model of the convection zone as well as f rom two basic models of a convective cell. We find that although solely dep th-dependent perturbations can give frequency shifts that are first order i n the strength of the perturbation, models of convective cells generate dow nward frequency shifts that are second order in the perturbation strength. These results may have implications for resolving the differences between e igenfrequencies derived from solar models and those found from helioseismic observations.