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arXiv · 2010.01686

The impact of composition choices on solar evolution: age, helio- and asteroseismology, and neutrinos

Abstract

The Sun is the most studied and well-known star, and as such, solar fundamental parameters are often used to bridge gaps in the knowledge of other stars, when these are required for modelling. However, the two most powerful and precise independent methodologies currently available to infer the internal solar structure are in disagreement. We aim to show the potential impact of composition choices in the overall evolution of a star, using the Sun as an example. To this effect, we create two Standard Solar Models and a comparison model using different combinations of metallicity and relative element abundances and compare evolutionary, helioseismic, and neutrino-related properties for each. We report differences in age for models calibrated to the same point in the HR diagram, in the red giant branch, of more than 1 Gyr, and found that the current precision level of asteroseismic measurements is enough to differentiate these models, which would exhibit differences in priod spacing of 1.30-2.58 per cent. Additionally, we show that the measurement of neutrino fluxes from the carbon-nitrogen-oxygen cycle with a precision of around 17 per cent, which could be achieved by the next generation of solar neutrino experiments, could help resolve the stellar abundance problem.

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Diogo Capelo, Ilídio Lopes. 2020-10-04. The impact of composition choices on solar evolution: age, helio- and asteroseismology, and neutrinos. https://doi.org/10.1093/mnras%2Fstaa2402

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