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arXiv · 2201.02889

Beta-delayed fission in the coupled Quasi-particle Random Phase Approximation plus Hauser-Feshbach approach

M. R. Mumpower·T. Kawano·T. M. Sprouse
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Abstract

Beta-delayed neutron emission and $\beta$-delayed fission ($\beta$df) probabilities were calculated for heavy, neutron-rich nuclei using the Los Alamos coupled Quasi-Particle Random Phase Approximation plus Hauser-Feshbach (QRPA+HF) approach. In this model, the compound nucleus is initially populated by $\beta$-decay and is followed through subsequent statistical decays taking into account competition between neutrons, $\gamma$-rays and fission. The primary output of these calculations includes branching ratios along with neutron and $\gamma$-ray spectra. We find a relatively large region of heavy nuclides where the probability of $\beta$df is near 100%. For a subset of nuclei near the neutron dripline, delayed neutron emission and the probability to fission are both large which leads to the possibility of multi-chance $\beta$df (mc-$\beta$df). We comment on prospective neutron-rich nuclei that could be probed by future experimental campaigns and provide a full table of branching ratios in ASCII format in the supplemental material for use in various applications.

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M. R. Mumpower, T. Kawano, T. M. Sprouse. 2022-01-08. Beta-delayed fission in the coupled Quasi-particle Random Phase Approximation plus Hauser-Feshbach approach. https://doi.org/10.1103/physrevc.106.065805

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