The Influence of a Modified Mixing-Length Theory and of an Adopted Description of the Atmosphere on the Solar Five-Minute Oscillations

Abstract

The influence of the modified treatment of subphotospheric convection, as recommended by Deupree (1979) and by Deupree and Varner (1980), on the frequencies of solar five-minute oscillations of degree 1 = 1–100 is studied. As compared with the results for a standard solar model, the convection theory modification has practically no effect on the frequencies near the low frequency edge of the observational interval (at ν ≃ 2000 μHz), but causes a frequency decrease for high overtones; the effect is larger at larger frequencies. At ν ≃ 4000 μHz the frequency decrease is about 4–6 μHz for all 1 ⩽ 40 and about 8–10 μHz for 1 ≃ 60–100. If, additionally, we use the dependence T(τ) according to Holweger and Müller (1974) instead of the HSRA model, the joint effect is 1.5–2 times larger. In this case the slope of the theoretical curves in “echelle diagrams” turns out to be in agreement with the observational one for 1 ⩽ 20, but the frequencies themselves are approximately 10 μHz lower than those from observations.