3D hydrodynamic simulations of C ingestion into a convective O shell
Abstract Interactions between convective shells in evolved massive stars have been linked to supernova impostors, to the production of the odd-Z elements Cl, K, and Sc, and they might also help generate the large-scale asphericities that are known to facilitate shock revival in supernova explosion models. We investigate the process of ingestion of C-shell material into a convective O-burning shell, including the hydrodynamic feedback from the nuclear burning of the ingested material. Our 3D hydrodynamic simulations span almost 3 dex in the total luminosity $L_\rm {tot}$. All but one of the simulations reach a quasi-stationary state with the entrainment rate and convective velocity proportional to $L_\rm {tot}$ and $L_\rm {tot}^{1/3}$, respectively. Carbon burning provides 14 – $33\%$ of the total luminosity, depending on the set of reactions considered. Equivalent simulations done on 7683 and 11523 grids are in excellent quantitative agreement. The flow is dominated by a few large-scale convective cells. An instability leading to large-scale oscillations with Mach numbers in excess of 0.2 develops in an experimental run with the energy yield from C burning increased by a factor of 10. This run represents most closely the conditions expected in a violent O-C shell merger, which is a potential production site more »
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Publication Date:
NSF-PAR ID:
10166281
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
491
Page Range or eLocation-ID:
972 - 992
ISSN:
0035-8711
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