1. Proton Shell Evolution below Sn-132: First Measurement of Low-Lying beta-Emitting Isomers in Ag-123,Ag-325
- Author
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Chen, ZQ, Li, ZH, Hua, H, Watanabe, H, Yuan, CX, Zhang, SQ, Lorusso, G, Nishimura, S, Baba, H, Browne, F, Benzoni, G, Chae, KY, Crespi, FCL, Doornenbal, P, Fukuda, N, Gey, G, Gernhaeuser, R, Inabe, N, Isobe, T, Jiang, DX, Jungclaus, A, Jung, HS, Jin, Y, Kameda, D, Kim, GD, Kim, YK, Kojouharov, I, Kondev, FG, Kubo, T, Kurz, N, Kwon, YK, Li, XQ, Lou, JL, Lane, GJ, Li, CG, Luo, DW, Montaner-Piza, A, Moschner, K, Niu, CY, Naqvi, F, Niikura, M, Nishibata, H, Odahara, A, Orlandi, R, Patel, Z, Podolyak, Zs, Sumikama, T, Soderstrom, P-A, Sakurai, H, Schaffner, H, Simpson, GS, Steiger, K, Suzuki, H, Taprogge, J, Takeda, H, Vajta, Zs, Wang, HK, Wu, J, Wendt, A, Wang, CG, Wu, HY, Wang, X, Wu, CG, Xu, C, Xu, ZY, Yagi, A, Ye, YL, and Yoshinaga, K
- Subjects
RIKEN ,Science & Technology ,IMPACT ,Physics ,Physical Sciences ,Physics, Multidisciplinary ,ISOTOPES ,DECAY - Abstract
The β-delayed γ-ray spectroscopy of neutron-rich ^{123,125}Ag isotopes is investigated at the Radioactive Isotope Beam Factory of RIKEN, and the long-predicted 1/2^{-} β-emitting isomers in ^{123,125}Ag are identified for the first time. With the new experimental results, the systematic trend of energy spacing between the lowest 9/2^{+} and 1/2^{-} levels is extended in Ag isotopes up to N=78, providing a clear signal for the reduction of the Z=40 subshell gap in Ag towards N=82. Shell-model calculations with the state-of-the-art V_{MU} plus M3Y spin-orbit interaction give a satisfactory description of the low-lying states in ^{123,125}Ag. The tensor force is found to play a crucial role in the evolution of the size of the Z=40 subshell gap. The observed inversion of the single-particle levels around ^{123}Ag can be well interpreted in terms of the monopole shift of the π1g_{9/2} orbitals mainly caused by the increasing occupation of ν1h_{11/2} orbitals. ispartof: PHYSICAL REVIEW LETTERS vol:122 issue:21 ispartof: location:United States status: published
- Published
- 2019