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Abstract Many of the short-lived radioactive nuclei that were present in the early solar system can be produced in massive stars. In the first paper in this series, we focused on the production of26Al in massive binaries. In our second paper, we considered rotating single stars; two more short-lived radioactive nuclei,36Cl and41Ca; and the comparison to the early solar system data. In this work, we update our previous conclusions by further considering the impact of binary interactions. We used the MESA stellar evolution code with an extended nuclear network to compute massive (10–80M⊙), binary stars at various initial periods and solar metallicity (Z= 0.014), up to the onset of core collapse. The early solar system abundances of26Al and41Ca can be matched self-consistently by models with initial masses ≥25M⊙, while models with initial primary masses ≥35M⊙can also match36Cl. Almost none of the models provide positive net yields for19F, while for22Ne the net yields are positive from 30M⊙and higher. This leads to an increase by a factor of approximately 4 in the amount of22Ne produced by a stellar population of binary stars, relative to single stars. In addition, besides the impact on the stellar yields, our 10M⊙primary star undergoing Case A mass transfer ends its life as a white dwarf instead of as a core-collapse supernova. This demonstrates that binary interactions can also strongly impact the evolution of stars close to the supernova boundary.
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Evolving massive stars to core collapse with GENEC: Extension of equation of state, opacities and effective nuclear network
Context.Stars with initial mass above roughly 8M⊙will evolve to form a core made of iron group elements, at which point no further exothermic nuclear reactions between charged nuclei may prevent the core collapse. Electron capture, neutrino losses, and the photo-disintegration of heavy nuclei trigger the collapse of these stars. Models at the brink of core collapse are produced using stellar evolution codes, and these pre-collapse models may be used in the study of the subsequent dynamical evolution (including their explosion as supernovae and the formation of compact remnants such as neutron stars or black holes). Aims.We upgraded the physical ingredients employed by the GENeva stellar Evolution Code, GENEC, so that it covers the regime of high-temperatures and high-densities required to produce the progenitors of core-collapse. Our ultimate goal is producing pre-supernova models with GENEC, not only right before collapse, but also during the late phases (silicon and oxygen burning). Methods.We have improved GENEC in three directions: equation of state, the nuclear reaction network, and the radiative and conductive opacities adapted for the computation of the advanced phases of evolution. We produce a small grid of pre-supernova models of stars with zero age main sequence masses of 15 M⊙, 20 M⊙, and 25 M⊙at solar and less than half solar metallicities. The results are compared with analogous models produced with the MESA code. Results.The global properties of our new models, particularly of their inner cores, are comparable to models computed with MESA and pre-existing progenitors in the literature. Between codes the exact shell structure varies, and impacts explosion predictions. Conclusions.Using GENEC with state-of-the-art physics, we have produced massive stellar progenitors prior to collapse. These progenitors are suitable for follow-up studies, including the dynamical collapse and supernova phases. Larger grids of supernova progenitors are now feasible, with the potential for further dynamical evolution.
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- Award ID(s):
- 1927130
- PAR ID:
- 10649108
- Publisher / Repository:
- EDP Sciences
- Date Published:
- Journal Name:
- Astronomy & Astrophysics
- Volume:
- 693
- ISSN:
- 0004-6361
- Page Range / eLocation ID:
- A93
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1051/0004-6361/202451816
