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Half-lives and pre-supernova weak interaction rates for nuclei away from the stability line

K. Kar·S. Chakravarti·A. Ray·S. Sarkar
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Abstract

A detailed model for the calculation of beta decay rates of the $fp$ shell nuclei for situations prevailing in pre-supernova and collapse phases of evolution of the core of massive stars leading to supernova explosion has been extended for electron-capture rates. It can also be used to determine the half-lives of neutron-rich nuclei in the $fp/fpg$ shell. The model uses an averaged Gamow-Teller (GT) strength function. But it can also use the experimental log ft values and GT strength function from $(n,p)$ reaction studies wherever available. The calculated rate includes contributions from each of the low-lying excited states of the mother including some specific resonant states ("back resonance") having large GT matrix elements.

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K. Kar, S. Chakravarti, A. Ray, S. Sarkar. 1998-06-26. Half-lives and pre-supernova weak interaction rates for nuclei away from the stability line. https://doi.org/10.1088/0954-3899%2F24%2F8%2F045

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