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arXiv · 1505.03182

Convection and convective overshooting in stars more massive than 10 $M_\odot$

Jin Jie·Chunhua Zhu·Guoliang Lv
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Abstract

In this paper, four sets of evolutionary models are computed with different values of the mixing length parameter $\alpha_{\rm p}$ and the overshooting parameter $\delta_{\rm ov}$. The properties of the convective cores and the convective envelopes are studied in the massive stars. We get three conclusions: First, the larger $\alpha_{\rm p}$ leads to enhancing the convective mixing, removing the chemical gradient, and increasing the convective heat transfer efficiency. Second, core potential $\phi_{\rm c} = M_{\rm c} / R_{\rm c}$ describes sufficiently the evolution of a star, whether it is a red or blue supergiant at central helium ignition. Third, the discontinuity of hydrogen profile above the hydrogen burning shell seriously affect the occurrence of blue loops in the Hertzsprung--Russell diagram.

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Jin Jie, Chunhua Zhu, Guoliang Lv. 2015-05-12. Convection and convective overshooting in stars more massive than 10 $M_\odot$. https://arxiv.org/abs/1505.03182

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