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arXiv · 1302.0959

Shell evolution of N=20 nuclei and Gamow-Teller strengths of $^{30,32,34}$Mg by the deformed QRPA

Eunja Ha·Myung-Ki Cheoun
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Abstract

Gamow-Teller (GT) strength distributions of Mg isotopes are investigated within a framework of the deformed quasi-particle random phase approximation(DQRPA). We found that the N=20 shell closure in $^{28 \sim 34}$Mg was broken by the prolate shape deformation originating from the {\it fp}-intruder states. The shell closure breaking gives rise to a shift of low-lying GT excited states into high-lying states. Discussions regarding the shell evolution trend of single particle states around N=20 nuclei are also presented with the comparison to other approaches.

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Eunja Ha, Myung-Ki Cheoun. 2013-02-05. Shell evolution of N=20 nuclei and Gamow-Teller strengths of $^{30,32,34}$Mg by the deformed QRPA. https://arxiv.org/abs/1302.0959

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