The Run of Superadiabaticity in Stellar Convection Zones. I. The Sun

Abstract

The effect of adjustments to the superadiabatic layer (SAL) in a model of the Sun on the p-mode oscillation frequencies has been studied. Numerical simulations of solar convection by Kim and coworkers have shown that the usual mixing length approximation (MLA) overestimates the convective efficiency in the SAL. To correct for the overestimated convective efficiency in the calculation of the temperature gradient and the mean structure of the SAL, we have adopted a variable mixing length parameter, which decreases as the surface is approached, based on a simple parameterization suggested by the simulations. We find that these changes to the structure of the SAL reduce the discrepancies between observed and calculated oscillation frequencies in the low to intermediate l range.