Abstract
In this paper, the role of the mass distribution of fission fragments in the formation of heavy elements is considered. Two models of the mass distribution of fission fragments have been analyzed in detail: the Kodama–Takahashi model with a predominantly asymmetric distribution, and a model based on nuclear systematics with an almost symmetric distribution of fission remnants, which considers fission neutrons. It is shown that, in the merger scenario of a neutron star, the agreement between the second peak on the calculated abundance curve and observations can be obtained only if the distribution of fission remnants is symmetrical and fission neutrons are accounted for.
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ACKNOWLEDGMENTS
The authors thank F.-K. Thielemann and M. Eichler for helpful discussions of the physical processes affecting the formation of peaks on the heavy-nucleus abundance curve.
Funding
The work was supported by the Russian Science Foundation (project no. 21-12-00061).
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Translated by G. Dedkov
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Panov, I.V. Fission-Fragment Mass Distribution and Heavy Nuclei Nucleosynthesis. Phys. Part. Nuclei 54, 542–546 (2023). https://doi.org/10.1134/S1063779623030267
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DOI: https://doi.org/10.1134/S1063779623030267