Properties of $\gamma$-decaying isomers and isomeric ratios in the $^{100}$Sn region

J. Park , R. Krücken , D. Lubos , R. Gernhäuser , M. Lewitowicz (1) , S. Nishimura , D.S. Ahn , H. Baba , B. Blank (2) , A. Blazhev , P. Boutachkov , F. Browne , I. Celikovic (1) , G. de France (1) , P. Doornenbal , T. Faestermann , Y. Fang , N. Fukuda , J. Giovinazzo (2) , N. Goel , M. Górska , H. Grawe , S. Ilieva , N. Inabe , T. Isobe , A. Jungclaus , D. Kameda , G.D. Kim , Y.-K. Kim , I. Kojouharov , T. Kubo , N. Kurz , G. Lorusso , K. Moschner , D. Murai , I. Nishizuka , Z. Patel , M.M. Rajabali , S. Rice , H. Sakurai , H. Schaffner , Y. Shimizu , L. Sinclair , P.-A. Söderström , K. Steiger , T. Sumikama , H. Suzuki , H. Takeda , Z. Wang , H. Watanabe , J. Wu , Z.Y. Xu

1 GANIL - Grand Accélérateur National d'Ions Lourds
2 CENBG - Centre d'Etudes Nucléaires de Bordeaux Gradignan

Half-lives and energies of γ rays emitted in the decay of isomeric states of nuclei in the vicinity of the doubly magic Sn100 were measured in a decay spectroscopy experiment at Rikagaku Kenkyusho (The Institute of Physical and Chemical Research) of Japan Nishina Center. The measured half-lives, some with improved precision, are consistent with literature values. Three new results include a 55-keV E2γ ray from a new (4+) isomer with T1/2=0.23(6)μs in Rh92, a 44-keV E2γ ray from the (15+) isomer in Ag96, and T1/2(6+)=13(2) ns in Cd98. Shell-model calculations of electromagnetic transition strengths in the (p1/2,g9/2) model space agree with the experimental results. In addition, experimental isomeric ratios were compared to the theoretical predictions derived with an abrasion-ablation model and the sharp cutoff model. The results agreed within a factor of 2 for most isomers. From the nonobservation of time-delayed γ rays in Sn100, new constraints on the T1/2, γ-ray energy, and internal conversion coefficients are proposed for the hypothetical isomer in Sn100.

Domaines: Physique Nucléaire Expérimentale [nucl-ex]

J. Park, R. Krücken, D. Lubos, R. Gernhäuser, M. Lewitowicz, et al.. Properties of $\gamma$-decaying isomers and isomeric ratios in the $^{100}$Sn region. Phys.Rev.C, 2017, 96 (4), pp.044311. ⟨10.1103/PhysRevC.96.044311⟩. ⟨hal-01645716⟩