High-spin structure in Os

Shizuma, Toshiyuki; Mitarai, Shiro*; Sletten, G.*; Bark, R. A.*; Gjorup, N. L.*; Jensen, H. J.*; Piiparinen, M.*; Wrzesinski, J.*; Shimizu, Yoshifumi*

Physical Review C, 69(2), p.024305_1 - 024305_18, 2004/02

https://doi.org/10.1103/PhysRevC.69.024305

High-spin states in Os have been studied using the Yb(C,4n) reaction at a beam energy of 65MeV. Previously known 1-quasiparticle bands have been extended to higher spins. New high- bands based on 3- and 5-quasiparticle excitation have been identified. Nilsson configurations are assigned based on the g-factors deduced from M1/E2 branching ratios within the bands. In addition, a new isomer at 5008keV has been found with a half-life of 18(2) ns. The hindrance in decays of the high- intrinsic states are discussed in terms of the tunneling model where the low- and high- states interact through the triaxial shape fluctuation.