R-Process Freezeout, Nuclear Deformation, and the Rare-Earth Element Peak

R. Surman; J. Engel; J. R. Bennett; B. S. Meyer

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arXiv · astro-ph/9701007

R-Process Freezeout, Nuclear Deformation, and the Rare-Earth Element Peak

R. Surman·J. Engel·J. R. Bennett·B. S. Meyer

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Abstract

We use network calculations of r-process nucleosynthesis to explore the origin of the peak in the solar r-process abundance distribution near nuclear mass number A = 160. The peak is due to a subtle interplay of nuclear deformation and beta decay, and forms not in the steady phase of the r-process, but only just prior to freezeout, as the free neutrons rapidly disappear. Its existence should therefore help constrain the conditions under which the r-process occurs and freezes out.

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R. Surman, J. Engel, J. R. Bennett, B. S. Meyer. 1997-01-03. R-Process Freezeout, Nuclear Deformation, and the Rare-Earth Element Peak. https://arxiv.org/abs/astro-ph/9701007

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