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arXiv · 2211.01050

Nuclei in Core-Collapse Supernovae Engine

Abstract

Herein, we review the nuclear equations of state (EOSs) %for core-collapse supernova simulations and the constituent nuclei of core-collapse supernovae (CCSNe) and their roles in CCSN simulations. Various nuclei such as deuterons, iron, and extremely neutron-rich nuclei compose in the central engines of CCSNe. The center of a collapsing core is dominated by neutron-rich heavy nuclei prior to the occurrence of core bounce. Their weak interactions significantly affect the neutrino emission and the size of the produced proto-neutron star. After a core bounce, heavy nuclei are dissolved to protons, neutrons, and light nuclei between the expanding shock wave and the newly formed neutron star (NS). Some of the key components in determining the shock-wave dynamics and supernova explosion of outer envelopes are neutrino interactions of nucleons and light nuclei such as deuterons. An EOS provides the relations between thermodynamical properties and the nuclear composition, and is needed to simulate this explosion. Further investigations on uniform and non-uniform nuclear matter are needed to improve the understanding of the mechanism of CCSNe and the properties of supernova nuclei. The knowledge of the EOS for uniform nuclear matter is being continually improved by a combination of microscopic calculations, terrestrial experiments, and NS observations. With reference to various nuclear experiments and current theories, the finite temperature effects on heavy nuclei, formation of light nuclei in dilute nuclear matter, and transition to uniform nuclear matter should be improved in the model of the EOS for non-uniform nuclear matter.

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Shun Furusawa, Hiroki Nagakura. 2022-11-02. Nuclei in Core-Collapse Supernovae Engine. https://doi.org/10.1016/j.ppnp.2022.104018

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