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arXiv · 1407.0444

Nature of isomerism in exotic sulfur isotopes

Yutaka Utsuno·Noritaka Shimizu·Takaharu Otsuka·Tooru Yoshida·Yusuke Tsunoda
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Abstract

We clarify the origin of the anomalously hindered $E2$ decay from the $4^+_1$ level in $^{44}$S by performing a novel many-body analysis in the shell model. Within a unified picture about the occurrence of isomerism in neutron-rich sulfur isotopes, the $4^+_1$ state is demonstrated to be a $K=4$ isomer dominated by the two-quasiparticle configuration $\nu\Omega^{\pi}=1/2^-\otimes\nu\Omega^{\pi}=7/2^-$. The $4^+_1$ state in $^{44}$S is a new type of high-$K$ isomer which has significant triaxiality.

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Yutaka Utsuno, Noritaka Shimizu, Takaharu Otsuka, Tooru Yoshida, Yusuke Tsunoda. 2014-07-02. Nature of isomerism in exotic sulfur isotopes. https://doi.org/10.1103/physrevlett.114.032501

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