Rotational bands inX.H. Zhou1, M. Oshima2, Y. Toh2, Y.H. Zhang1, Y. Zheng1, M. Koizumi2, A. Osa2, T. Hayakawa2, Y. Hatsukawa2, T. Shizuma2 and M. Sugawara3
1 Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, PRC
2 Japan Atomic Energy Research Institute, Tokai, Ibaraki 319-1195, Japan
3 Chiba Institute of Technology, Narashino, Chiba 275-0023, Japan
(Received: 10 May 2002 / Revised version: 8 July 2002 / Published online: 19 November 2002)
High-spin states in 169Re have been investigated by means of in-beam -ray spectroscopy techniques with the 144Sm( 28Si, 1p2n ) 169Re reaction. X- and - - t coincidences, -ray anisotropies, and DCO ratios were measured. A strongly coupled band based on the 9/2 - Nilsson state and a decoupled band built on the h9/2 intruder proton orbital (nominally 1/2 -) have been established. The AB neutron crossings are observed at and 0.27 MeV for the 9/2 - and 1/2 - bands, respectively. The 9/2 - band in 169Re shows the largest signature splitting at low spin among the odd-mass Re isotopes. Band properties of the AB neutron crossing frequencies, alignment gains, and signature splittings are discussed, and compared with those in the heavier odd- A Re isotopes. Additionally, a three-quasipariticle band is observed, and the 9/2 configuration is proposed tentatively.
21.10.Re - Collective levels.
23.20.-g - Electromagnetic transitions.
23.20.Lv - Gamma transitions and level energies.
27.70.+q - .
© Società Italiana di Fisica, Springer-Verlag 2002