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arXiv · 2309.10490

Comparative study of low-temperature opacities with GARSTEC models

Pedro Diaz Reeve·Aldo Serenelli
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Abstract

We present a comparative study of the effect of low-temperature opacities on stellar models up to the Red Giant branch (RGB), computed with the GARching STellar Evolution Code. We have used two sets of low-temperature opacities; ÆSOPUS (Æ) from the University of Padova and those from the Wichita State University group (F05). In the relevant range of temperatures for this study, log \k{appa}Æ < log \k{appa}F 05. Therefore, to compare stellar evolutionary tracks, we performed a solar calibration of the αmlt, for each set of low-temperature opacities. After carrying such a calibration, we find that stellar evolutionary tracks are almost unaffected by the choice of low-temperature opacities, with largest variations of 25-30 K at the latest evolutionary stages of the RGB phase.

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Pedro Diaz Reeve, Aldo Serenelli. 2023-09-19. Comparative study of low-temperature opacities with GARSTEC models. https://doi.org/10.3847/2515-5172%2Facf9a2

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