The i-process yields of rapidly accreting white dwarfs from multicycle He-shell flash stellar evolution models with mixing parametrizations from 3D hydrodynamics simulations

Denissenkov, Pavel A; Herwig, Falk; Woodward, Paul; Andrassy, Robert; Pignatari, Marco; Jones, Samuel

Abstract

© 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society We have modelled the multicycle evolution of rapidly accreting CO white dwarfs (RAWDs) with stable H burning intermittent with strong He-shell flashes on their surfaces for 0.7 ≤ MRAWD/Mo ≤ 0.75 and [Fe/H] ranging from 0 to −2.6. We have also computed the i-process nucleosynthesis yields for these models. The i process occurs when convection driven by the He-shell flash ingests protons from the accreted H-rich surface layer, which results in maximum neutron densities Nn, max ≈ 1013–1015 cm−3. The H-ingestion rate and the convective boundary mixing (CBM) parameter ftop adopted in the one-dimensional nucleosynthesis and stellar evolution models are constrained through three-dimensional (3D) hydrodynamic simulations. The mass ingestion rate and, for the first time, the scaling laws for the CBM parameter ftop have been determined from 3D hydrodynamic simulations. We confirm our previous result that the high-metallicity RAWDs have a low mass retention efficiency (η

Citation

Denissenkov, P. A., Herwig, F., Woodward, P., Andrassy, R., Pignatari, M., & Jones, S. (2019). The i-process yields of rapidly accreting white dwarfs from multicycle He-shell flash stellar evolution models with mixing parametrizations from 3D hydrodynamics simulations. Monthly notices of the Royal Astronomical Society, 488(3), 4258-4270. https://doi.org/10.1093/mnras/stz1921

• Journal Article Type: Article
• Acceptance Date: Jul 7, 2019
• Online Publication Date: Jul 12, 2019
• Publication Date: Sep 21, 2019
• Deposit Date: Aug 14, 2019
• Publicly Available Date: Aug 14, 2019
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 1365-2966
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 488
• Issue: 3
• Pages: 4258-4270
• DOI: https://doi.org/10.1093/mnras/stz1921
• Keywords: Space and Planetary Science; Astronomy and Astrophysics
• Public URL: https://hull-repository.worktribe.com/output/2356798
• Publisher URL: https://academic.oup.com/mnras/article/488/3/4258/5531775
• Additional Information: This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2019 The authors Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.