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arXiv · 2204.08598

Solar calibration of $\alpha_{\rm MLT}$ using {\AE}SOPUS opacities in MESA

Giulia C Cinquegrana·Meridith Joyce
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Abstract

The simplistic but ubiquitous Mixing Length Theory (MLT) formalism is used to model convective energy transport within 1D stellar evolution calculations. The formalism relies on the free parameter $\alpha_{\rm MLT}$, which must be independently calibrated within each stellar evolution program and for any given set of physical assumptions. We present a solar calibration of $\alpha_{\text{MLT}}$ appropriate for use with the AESOPUS opacities, which have recently been made available for use with the MESA stellar evolution software. We report a calibrated value of $\alpha_{\rm MLT}=1.931$ and demonstrate the impact of using an appropriately calibrated value in simulations of a $3 M_{\odot}$ asymptotic giant branch star.

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Giulia C Cinquegrana, Meridith Joyce. 2022-04-19. Solar calibration of $\alpha_{\rm MLT}$ using {\AE}SOPUS opacities in MESA. https://arxiv.org/abs/2204.08598

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