Nature of isomerism in exotic sulfur isotopes

Utsuno, Yutaka   ; Shimizu, Noritaka*; Otsuka, Takaharu*; Yoshida, Toru*; Tsunoda, Yusuke*

In usual even-even nuclei, , , states are known to be connected via strong transitions. The recently observed state in the neutron-rich nucleus S has a strongly hindered transition to the state. We report the origin of this strong hindrance in this paper. While shell-model calculations reproduce the hindrance, their many-body wave functions are too complicated for one to understand the nature. In this study, we introduce a novel method to obtain wave functions in the intrinsic frame by performing the variation after angular-momentum projection. The , states are dominated by the usual state, whereas for the level the state is lower than state, which causes the hindrance. We also account for similar hindrance in S in this framework. The level is the lightest-mass high- isomer ever found.