Nuclear structure study for the neutron-rich nuclei beyond 132Sn: In-beam gamma-ray spectroscopy of 136Sn and 132Cd
RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
2 Research Center for Nuclear Physics, Osaka University, Ibaraki, Osaka 567-0047, Japan
3 Department of Physics, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Tokyo 152-8551, Japan
4 Center for Nuclear Study, University of Tokyo,RIKEN campus, Wako, Saitama 351-0198, Japan
5 Institute for Nuclear Research, H-4001 Debrecen, P.O. Box 51, Hungary
6 Department of Physics, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima, Tokyo 172-8501, Japan
7 Department of Physics, University of Hong Kong, Pokfulam Road, Hong Kong
8 School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China
9 Department of Physics, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033, Japan
* e-mail: firstname.lastname@example.org
Published online: 16 May 2018
The neutron-rich nuclei 136Sn and 132Cd have been studied in the purpose of nuclear structure for the nuclei beyond the doubly-magic nucleus 132Sn. The 2+1 → 0+ gs transitions were identified for these two nuclei using in-beam γ-ray spectroscopy in coincidence with one- and two-proton removal reactions, respectively, at the RIKEN Radioactive Isotope Beam Factory. The 2+ 1 state in 136Sn is found to be similar to that for 134Sn indicating the seniority scheme may also hold for the heavy tin isotopes beyond N = 82. For 132Cd, the 2+ 1 state provides the first spectroscopic information in the even-even nuclei locating in the region “southeast” of 132Sn and the result is discussed in terms of proton-neutron configuration mixing. In both these two nuclei, it was found that the valence neutrons play an essential role in their low-lying excitations.
© The Authors, published by EDP Sciences, 2018
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