The effects of yields from binary massive stars as functions of metallicity

E. Pepe; E. Spitoni; F. Matteucci; M. Palla

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arXiv · 2606.02731

The effects of yields from binary massive stars as functions of metallicity

E. Pepe·E. Spitoni·F. Matteucci·M. Palla

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Abstract

Massive stars in binary systems that undergo mass transfer during their lifetime have a different evolution from that of single stars, possibly affecting their chemical yields. While massive stars produce most of the metals in the Universe, only few studies have investigated the effects of massive binary stars on the chemical evolution of the Milky Way. Following the most recent studies on massive binary-stripped star yields as functions of metallicity, we aim at improving previous results based on single-metallicity model grids. Here, by adopting a detailed model of chemical evolution for our Galaxy, we compute the evolution of 22 chemical species including C, N, O, $\alpha$-elements and Fe-peak elements, adopting novel prescriptions for single and binary massive star yields. Our main results can be summarised as follows: (i) consistently with previous predictions, we observe very small differences in both the predicted solar abundances and [X/Fe] vs [Fe/H] relations even when including massive binary yields depending on metallicity; (ii) when adopting the new set of stellar yields for massive single stars, as computed by Farmer et al. (2023), we are able to reproduce both the K solar abundance as well as the [K/Fe] vs [Fe/H] relation, without invoking ad hoc assumptions on nucleosynthesis prescriptions; (iii) our model adopting Farmer's yields both for single and binary massive stars is able to better reproduce the [X/Fe] versus [Fe/H] relation for both Mg and Ca, as compared with standard nucleosynthetic yields adopted in chemical evolution models; iv) we find that no models can well reproduce the [C/Fe] and [Ti/Fe] vs [Fe/H] when adopting the new yields as functions of metallicity.

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E. Pepe, E. Spitoni, F. Matteucci, M. Palla. 2026-06-01. The effects of yields from binary massive stars as functions of metallicity. https://arxiv.org/abs/2606.02731

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