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arXiv · 1608.01956

Neutron-gamma competition for $\beta$-delayed neutron emission

Matthew Mumpower·Toshihiko Kawano·Peter Moller
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Abstract

We present a coupled Quasi-particle Random Phase Approximation and Hauser-Feshbach (QRPA+HF) model for calculating delayed particle emission. This approach uses microscopic nuclear structure information which starts with Gamow-Teller strength distributions in the daughter nucleus, and then follows the statistical decay until the initial available excitation energy is exhausted. Explicitly included at each particle emission stage is $\gamma$-ray competition. We explore this model in the context of neutron emission of neutron-rich nuclei and find that neutron-gamma competition can lead to both increases and decreases in neutron emission probabilities, depending on the system considered. A second consequence of this formalism is a prediction of more neutrons on average being emitted after $\beta$-decay for nuclei near the neutron dripline compared to models that do not consider the statistical decay.

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Matthew Mumpower, Toshihiko Kawano, Peter Moller. 2016-08-05. Neutron-gamma competition for $\beta$-delayed neutron emission. https://doi.org/10.1103/physrevc.94.064317

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