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arXiv · 1812.00431

Model physics in low-mass solar-type stars: atomic diffusion and metallicity mixture

Benard Nsamba·Tiago L. Campante·Mário J. P. F. G. Monteiro·Margarida S. Cunha·Ben M. Rendle·Daniel R. Reese·Kuldeep Verma
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Abstract

Using asteroseismic data from the Kepler satellite, we explore the systematic uncertainties arising from changes in the input physics used when constructing evolution models of solar-type stars. We assess the impact of including atomic diffusion and of varying the metallicity mixture on the determination of global stellar parameters (i.e., radius, mass, and age). We find significant systematic uncertainties on global stellar parameters when diffusion is included in stellar grids. Furthermore, we find the systematic uncertainties on the global stellar parameters to be comparable to the statistical uncertainties when a different metallicity mixture is employed in stellar grids.

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Benard Nsamba, Tiago L. Campante, Mário J. P. F. G. Monteiro, Margarida S. Cunha, Ben M. Rendle, Daniel R. Reese, Kuldeep Verma. 2018-12-02. Model physics in low-mass solar-type stars: atomic diffusion and metallicity mixture. https://doi.org/10.5281/zenodo.1468510

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