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arXiv · 2502.05025

Impact of radiative accelerations on the stellar characterization of FGK-type stars using spectroscopic and seismic constraints

Nuno Moedas·Morgan Deal·Diego Bossini
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Abstract

Chemical transport mechanisms are fundamental processes in stellar evolution models. They are responsible for the chemical distribution, and their impact determines how accurately we can characterize stars. Radiative accelerations are one of these processes. They allow the accumulation of elements at different depths in the star. We aim to assess the impact of radiative accelerations on the modeling of FGK-type stars and their impact on the prediction of surface abundances. To reduce the cost of the computation of radiative accelerations, we implemented the single-valued parameters (SVP) method in the stellar evolution code MESA. The SVP method is more efficient in calculating radiative accelerations, which enables computations of large enough grids of models for stellar characterization. Compared to models that include atomic diffusion (with only gravitational settling), the inclusion of radiative accelerations has a small effect on the inference of fundamental properties, with an impact of 2\%, 0.7\%, and 5\% for mass, radius, and age. However, the treatment of radiative accelerations is necessary to predict the chemical composition of and accurately characterize stars.

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Nuno Moedas, Morgan Deal, Diego Bossini. 2025-02-07. Impact of radiative accelerations on the stellar characterization of FGK-type stars using spectroscopic and seismic constraints. https://arxiv.org/abs/2502.05025

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