Turbulent Convection Model in the Overshooting Region. I. Effects of the Convective Mixing in the Solar Overshooting Region

Abstract

The overshooting in the framework of the turbulent convection model is investigated in the solar overshooting region. The overshooting mixing is treated as a diffusive process. It is found that the sound speed profile can be improved to be in good agreement with helioseismic inversions. The bump in the sound speed differences between solar models and the helioseismical inversions below the base of the solar convective envelope is almost eliminated by the overshooting mixing. The overshooting mixing leads to a significant depletion of Li in the main-sequence stage. Li abundance in the solar surface can be reduced to about 1% of its initial abundance in the solar models with the overshooting mixing. The solar model with the overshooting shows a smooth profile of the temperature gradient, which is also favored by the helioseismology.