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arXiv · 2412.19521

Impact of dineutrons on nuclear compositions of a core-collapse supernova

Tatsuya Matsuki·Shun Furusawa·Katsuhiko Suzuki
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Abstract

We study the nuclear compositions in the central region of a core-collapse supernova, assuming the existence of dineutrons ($^2n$) and tetraneutrons ($^4n$). At 100~ms after core bounce, ${}^2n$ and ${}^4n$ are more abundant than deuterons within radii of approximately 100 and 50~km, respectively. Compared to the model ignoring the existence of ${}^2n$ and ${}^4n$, the mass fraction of neutrons up to a radius of 100~km reduces, while the mass fractions of protons, deuterons, and $\rm{{}^4He}$ increase. Due to the uncertainties in the properties of $^2n$ and $^4n$, we investigate the influence of their binding energies on the nuclear composition. We find the binding energy of $^2n$ has only a modest effect on the overall composition, except for its own mass fraction, while that of $^4n$ has a negligible impact.

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Tatsuya Matsuki, Shun Furusawa, Katsuhiko Suzuki. 2024-12-27. Impact of dineutrons on nuclear compositions of a core-collapse supernova. https://doi.org/10.1103/733q-k218

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