Waves in structured media: non-radial solar p modes

For non-radial solar p modes we calculate corrections to the eigenfrequencies arising from the sound speed and velocity inhomogeneity of the convection zone. We use a simple periodic model, and obtain the frequency corrections by solving a Hill determinant. The frequency shifts are significant, and in most cases negative; they increase in magnitude with increasing frequency and harmonic degree l. The dependence on degree scales with the mode inertia. For large degree l this trend reverses. For very large degree coupling occurs between the p modes and "vibrational" modes that only exist because of the horizontal structure in sound speed and velocity.