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Seismic diagnostics on stellar convection treatment from oscillation amplitudes of p-modes

R. Samadi·M. J. Goupil·Y. Lebreton·A. Nordlund·F. Baudin
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Abstract

The excitation rate P of solar p-modes is computed with a model of stochatic excitation which involves constraints on the averaged properties of the solar turbulence. These constraints are obtained from a 3D simulation. Resulting values for P are found ~9 times larger than when the calculation assumes properties of turbulent convection which are derived from an 1D solar model based on Gough (1977)'s formulation of the mixing-length theory (GMLT). This difference is mainly due to the assumed values for the mean anisotropy of the velocity field in each case.Calculations based on 3D constraints bring the P maximum closer to the observational one.We also compute P for several models of intermediate mass stars (1Mo < M < 2Mo). Differences in the values of P_max between models computed with the classical mixing-length theory and GMLT models are found large enough for main sequence stars to suggest that measurements of P in this mass range will be able to discriminate between different models of turbulent convection.

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R. Samadi, M. J. Goupil, Y. Lebreton, A. Nordlund, F. Baudin. 2002-10-01. Seismic diagnostics on stellar convection treatment from oscillation amplitudes of p-modes. https://arxiv.org/abs/astro-ph/0210036

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