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arXiv · 1309.0540

Statistical Global Model of beta- Half-lives and r-Process Nucleosynthesis

N. J. Costiris·E. Mavrommatis·K. A. Gernoth·J. W. Clark
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Abstract

Purpose: Our objective is to apply an improved statistical global model of beta^- decay half-life systematics [1] generated by machine-learning techniques to the prediction of beta half-lives relevant to r-process nuclei. The primary aim of this application is to complement existing r-process-clock and matter-flow studies, thereby providing additional theoretical support for the planning of future activities of the world's network of rare-isotope laboratories. Results: Results are presented for nuclides situated on the r-ladders at N=50, 82, and 126 where abundances peak, as well as for nuclides that affect abundances between peaks or may be relevant to r-processes under different astrophysical scenarios. The half-lives of some of the targeted neutron-rich nuclides have either been recently measured or will be accessible at rare-isotope laboratories in the relatively near future. The results of our large-scale data-driven half-life calculations (generated by a "theory-thin" global statistical model) are compared to available experimental data, including recent measurements on very neutron-rich nuclei along an r-process path far from the valley of $β$ stability. Comparison is also made with corresponding results from traditional global models derived by semi-phenomenological "theory-thick" approaches.

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N. J. Costiris, E. Mavrommatis, K. A. Gernoth, J. W. Clark. 2013-09-02. Statistical Global Model of beta- Half-lives and r-Process Nucleosynthesis. https://arxiv.org/abs/1309.0540

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