Köln 2025 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
HK: Fachverband Physik der Hadronen und Kerne
HK 12: Nuclear Astrophysics II
HK 12.4: Talk
Monday, March 10, 2025, 17:45–18:00, SR 0.03 Erw. Physik
Multidimensional Hydrodynamical Simulations of Thermonuclear Ignition in Oxygen-Neon-Carbon Cores — •Paul Christians1,2, Gabriel Martínez-Pinedo1,2, Friedrich Konrad Röpke3,4, Giovanni Leidi3, and Róbert Andrássy4,3 — 1GSI Helmholtzzentrum für Schwerionenforschung — 2Institut für Kernphysik, TU Darmstadt — 3Heidelberger Institut für Theoretische Studien HITS gGmbH — 4Zentrum für Astronomie der Universität Heidelberg
The fate of intermediate-mass stars (7−11 M⊙) depends on the evolution of their degenerate oxygen-neon cores, formed from the ashes of prior core carbon burning. Their evolution is mainly driven by electron capture reactions, which either cool or heat the core significantly, potentially determining the final fate of the star. Recently, it has been shown that forbidden electron capture transitions play a key role in the relevant temperature-density regimes, significantly altering the temperature evolution. Furthermore, residual carbon could lead to oxygen ignition at significantly lower densities. The ignition of this residual carbon is triggered by exothermic double electron capture on 24Mg and 24Na, which also heavily relies on the correct inclusion of forbidden rates and the treatment of convection. We study the impact of those key forbidden transitions using a low Mach multidimensional hydrodynamical code called Seven-League Hydro (SLH). This is needed, as highly subsonic convective flows play a crucial role during the final evolution. DFG Project-ID MA 4248/3-1; RO 3676/7-1. We acknowledge support by the Klaus Tschira Foundation.
Keywords: Simulation; Hydrodynamics; Electron-Capture; Stellar Evolution