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arXiv · 1502.04836

Gamow-Teller response and its spreading mechanism in doubly magic nuclei

Yifei Niu·Gianluca Colo·Enrico Vigezzi
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Abstract

The scope of the paper is to apply a state-of-the-art beyond mean-field model to the description of the Gamow-Teller response in atomic nuclei. This topic recently attracted considerable renewed interest, due, in particular, to the possibility of performing experiments in unstable nuclei. We study the cases of $^{48}$Ca, $^{78}$Ni, $^{132}$Sn and $^{208}$Pb. Our model is based on a fully self-consistent Skyrme Hartree-Fock plus random phase approximation. The same Skyrme interaction is used to calculate the coupling between particles and vibrations, which leads to the mixing of the Gamow-Teller resonance with a set of doorway states and to its fragmentation. We compare our results with available experimental data. The microscopic coupling mechanism is also discussed in some detail.

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Yifei Niu, Gianluca Colo, Enrico Vigezzi. 2015-02-17. Gamow-Teller response and its spreading mechanism in doubly magic nuclei. https://doi.org/10.1103/physrevc.90.054328

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