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Excitation rates of p modes: mass luminosity relation across the HR diagram

R. Samadi·D. Georgobiani·R. Trampedach·M. J. Goupil·R. F. Stein·A. Nordlund
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Abstract

We compute the rates P at which energy is injected into the p modes for a set of 3D simulations of outer layers of stars. We found that Pmax - the maximum in P - scales as (L/M)^s where s is the slope of the power law, L and M are the luminosity and the mass of the 1D stellar models associated with the simulations. The slope is found to depend significantly on the adopted representation for the turbulent eddy-time correlation function, chi_k. According to the expected performances of COROT, it will likely be possible to measure Pmax as a function of L/M and to constrain the properties of stellar turbulence as the turbulent eddy time-correlation.

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R. Samadi, D. Georgobiani, R. Trampedach, M. J. Goupil, R. F. Stein, A. Nordlund. 2004-10-02. Excitation rates of p modes: mass luminosity relation across the HR diagram. https://arxiv.org/abs/astro-ph/0410043

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