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arXiv · 1410.0614

Influence of 2p-2h configurations on beta-decay rates

A. P. Severyukhin·V. V. Voronov·I. N. Borzov·N. N. Arsenyev·Nguyen Van Giai
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Abstract

The effects of the phonon-phonon coupling on the beta-decay rates of neutron-rich nuclei are studied in a microscopic model based on Skyrme-type interactions. The approach uses a finite-rank separable approximation of the Skyrme-type particle-hole (p-h) residual interaction. Very large two-quasiparticle spaces can thus be treated. A redistribution of the Gamow-Teller (G-T) strength is found due to the tensor correlations and the 2p-2h fragmentation of G-T states. As a result, the beta-decay half-lives are decreased significantly. Using the Skyrme interaction SGII together with a volume-type pairing interaction we illustrate this reduction effect by comparing with available experimental data for the Ni isotopes and neutron-rich N=50 isotones. We give predictions for 76Fe and 80Ni in comparison with the case of the doubly-magic nucleus 78Ni which is an important waiting point in the r-process.

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A. P. Severyukhin, V. V. Voronov, I. N. Borzov, N. N. Arsenyev, Nguyen Van Giai. 2014-10-02. Influence of 2p-2h configurations on beta-decay rates. https://doi.org/10.1103/physrevc.90.044320

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