Stellar Evolution in the Early Universe

Hirschi, R.; Frischknecht, U.; -K. Thielemann, F.; Pignatari, M.; Chiappini, C.; Ekstroem, S.; Meynet, G.; Maeder, A.

Abstract

Massive stars played a key role in the early evolution of the Universe. They formed with the first halos and started the re-ionisation. It is therefore very important to understand their evolution. In this paper, we describe the strong impact of rotation induced mixing and mass loss at very low $Z$. The strong mixing leads to a significant production of primary nitrogen 14, carbon 13 and neon 22. Mass loss during the red supergiant stage allows the production of Wolf-Rayet stars, type Ib,c supernovae and possibly gamma-ray bursts (GRBs) down to almost Z=0 for stars more massive than 60 solar masses. Galactic chemical evolution models calculated with models of rotating stars better reproduce the early evolution of N/O, C/O and C12/C13. We calculated the weak s-process production induced by the primary neon 22 and obtain overproduction factors (relative to the initial composition, Z=1.e-6) between 100-1000 in the mass range 60-90.

Citation

Hirschi, R., Frischknecht, U., -K. Thielemann, F., Pignatari, M., Chiappini, C., Ekstroem, S., Meynet, G., & Maeder, A. (2008). Stellar Evolution in the Early Universe. Proceedings of the International Astronomical Union, 4(S255), https://doi.org/10.1017/S1743921308024976

• Journal Article Type: Article
• Online Publication Date: Jun 1, 2008
• Publication Date: Jun 1, 2008
• Deposit Date: Jul 7, 2023
• Publicly Available Date: Jul 7, 2023
• Journal: Proceedings of the International Astronomical Union
• Print ISSN: 1743-9213
• Electronic ISSN: 1743-9221
• Publisher: Cambridge University Press
• Peer Reviewed: Peer Reviewed
• Volume: 4
• Issue: S255
• DOI: https://doi.org/10.1017/S1743921308024976
• Keywords: Astrophysics; Stars: mass loss; stars: Population II; stars: rotation; stars: supernovae; stars: Wolf-Rayet; Galaxy: evolution
• Public URL: https://keele-repository.worktribe.com/output/506739