Multi-quasiparticle states and K-forbidden transitions in 183Os

✍ Scribed by T. Shizuma; K. Matsuura; Y. Toh; Y. Hayakawa; M. Oshima; Y. Hatsukawa; M. Matsuda; K. Furuno; Y. Sasaki; T. Komatsubara; Y.R. Shimizu

• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 468 KB
• Volume: 696
• Category: Article
• ISSN: 0375-9474
• DOI: 10.1016/s0375-9474(01)01210-6

✦ Synopsis

High-spin states in 183 Os have been studied using the 170 Er( 18 O, 5n) reaction at a beam energy of 85 MeV. Nine rotational bands based on 1-, 3-, 5-and 7-quasiparticle excitations have been observed. Nilsson configurations are assigned for the newly observed bands using g-factors deduced from M1/E2 branching ratios within the bands. In addition, two isomers with K π = (43/2 + ) and (43/2 -) have been identified. The K π = (43/2 + ) isomer decays directly to the K π = 9/2 + ground-state band with a large difference in the K quantum number, K = 17. The decay rates are discussed in terms of a tunneling model where high-K (isomeric) and low-K states interact via fluctuations towards triaxial nuclear shapes.