Convective–reactive nucleosynthesis of K, Sc, Cl and p-process isotopes in O–C shell mergers

Ritter, C.; Andrassy, R.; Côté, B.; Herwig, F.; Woodward, P. R.; Pignatari, M.; Jones, S.

Abstract

© 2017 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. We address the deficiency of odd-Z elements P, Cl, K and Sc in Galactic chemical evolution models through an investigation of the nucleosynthesis of interacting convective O and C shells in massive stars. 3D hydrodynamic simulations of O-shell convection with moderate C-ingestion rates show no dramatic deviation from spherical symmetry. We derive a spherically averaged diffusion coefficient for 1D nucleosynthesis simulations, which show that such convective-reactive ingestion events can be a production site for P, Cl, K and Sc. An entrainment rate of 10-3M⊙s-1features overproduction factors OPs≈ 7. Full O-C shell mergers in our 1D stellar evolution massive star models have overproduction factors OPm> 1 dex but for such cases 3D hydrodynamic simulations suggest deviations from spherical symmetry. γ - process species can be produced with overproduction factors of OPm> 1 dex, for example, for130, 132Ba. Using the uncertain prediction of the 15M⊙, Z = 0.02 massive star model (OPm≈ 15) as representative for merger or entrainment convective-reactive events involving O- and C-burning shells, and assume that such events occur in more than 50 per cent of all stars, our chemical evolution models reproduce the observed Galactic trends of the odd-Z elements.

Citation

Ritter, C., Andrassy, R., Côté, B., Herwig, F., Woodward, P. R., Pignatari, M., & Jones, S. (2018). Convective–reactive nucleosynthesis of K, Sc, Cl and p-process isotopes in O–C shell mergers. Monthly notices of the Royal Astronomical Society. Letters, 474(1), L1-L6. https://doi.org/10.1093/mnrasl/slx126

• Journal Article Type: Article
• Acceptance Date: Aug 1, 2017
• Online Publication Date: Aug 3, 2017
• Publication Date: Feb 11, 2018
• Deposit Date: Mar 18, 2018
• Publicly Available Date: Mar 19, 2018
• Journal: MNRAS Letters
• Electronic ISSN: 1745-3933
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 474
• Issue: 1
• Pages: L1-L6
• DOI: https://doi.org/10.1093/mnrasl/slx126
• Keywords: Stars -- abundances; Stars -- evolution; Stars -- interiors; Physical data and processes; Hydrodynamics; Galaxy -- abundances
• Public URL: https://hull-repository.worktribe.com/output/586958
• Publisher URL: https://academic.oup.com/mnrasl/article/474/1/L1/4062155
• Related Public URLs: https://arxiv.org/abs/1704.05985
• Additional Information: This is a pre-copyedited, author-produced PDF of an article accepted for publication in MNRAS following peer review. The version of record is not currently available.
• Contract Date: Mar 18, 2018