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arXiv · 1810.04932

Two-phonon structures for beta-decay theory

A. P. Severyukhin·N. N. Arsenyev·I. N. Borzov·R. G. Nazmitdinov·S. Åberg
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Abstract

The $β$-decay rates of $^{60}$Ca have been studied within a microscopic model, which is based on the Skyrme interaction T45 to construct single-particle and phonon spaces. We observe a redistribution of the Gamow-Teller strength due to the phonon-phonon coupling, considered in the model. For $^{60}$Sc, the spin-parity of the ground state is found to be $1^+$. We predict that the half-life of $^{60}$Ca is 0.3 ms, while the total probability of the $βx n$ emission is 6.1%. Additionally, the random matrix theory has been applied to analyse the statistical properties of the $1^+$ spectrum populated in the $β$-decay to elucidate the obtained results.

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A. P. Severyukhin, N. N. Arsenyev, I. N. Borzov, R. G. Nazmitdinov, S. Åberg. 2018-10-11. Two-phonon structures for beta-decay theory. https://doi.org/10.1051/epjconf%2F201819402008

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