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Abstract Radioactive nuclei were present in the early solar system (ESS), as inferred from analysis of meteorites. Many are produced in massive stars, either during their lives or their final explosions. In the first paper of this series (Brinkman et al. 2019), we focused on the production of 26 Al in massive binaries. Here, we focus on the production of another two short-lived radioactive nuclei, 36 Cl and 41 Ca, and the comparison to the ESS data. We used the MESA stellar evolution code with an extended nuclear network and computed massive (10–80 M ⊙ ), rotating (with initial velocities of 150 and 300 km s −1 ) and nonrotating single stars at solar metallicity ( Z = 0.014) up to the onset of core collapse. We present the wind yields for the radioactive isotopes 26 Al, 36 Cl, and 41 Ca, and the stable isotopes 19 F and 22 Ne. In relation to the stable isotopes, we find that only the most massive models, ≥60 and ≥40 M ⊙ give positive 19 F and 22 Ne yields, respectively, depending on the initial rotation rate. In relation to the radioactive isotopes, we find that the ESS abundances of 26 Al and 41 Ca can be matched with by models with initial masses ≥40 M ⊙ , while 36 Cl is matched only by our most massive models, ≥60 M ⊙ . 60 Fe is not significantly produced by any wind model, as required by the observations. Therefore, massive star winds are a favored candidate for the origin of the very short-lived 26 Al, 36 Cl, and 41 Ca in the ESS.
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Aluminium-26 from Massive Binary Stars. III. Binary Stars up to Core Collapse and Their Impact on the Early Solar System
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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- Award ID(s):
- 1927130
- PAR ID:
- 10429996
- Publisher / Repository:
- DOI PREFIX: 10.3847
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 951
- Issue:
- 2
- ISSN:
- 0004-637X
- Format(s):
- Medium: X Size: Article No. 110
- Size(s):
- Article No. 110
- Sponsoring Org:
- National Science Foundation
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