Eur. Phys. J. A 14, 133-136 (2002)
Shape co-existence and structural evolution of the yrast band inY. Zheng1, X.H. Zhou1, Y.H. Zhang1, Y.X. Guo1, X.G. Lei1, Z. Liu1, J.J. He1, M.L. Liu1, W.J. Luo1, S.X. Wen2, L.H. Zhu2 and C.X. Yang2
1 Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, PRC
2 China Institute of Atomic Energy, Beijing 102413, PRC
(Received: 7 January 2002 / Revised version: 10 April 2002 Communicated by D. Schwalm)
The high-spin states of 157Yb have been studied via the 144Sm( 16 O, 3n) reaction at 16O energy of 90 MeV using techniques of in-beam -ray spectroscopy. Measurement of - - t coincidences was performed with 11 BGO(AC)HPGe detectors. Based on the measured results of - coincidences, -ray anisotropies and DCO ratios, the level scheme for 157Yb was established. The shape co-existence and structural evolution of the band with increasing angular momentum in 157Yb have been discussed. The systematics of the bands in the N=87 odd- A isotones have been compared.
23.20.Lv - Gamma transitions and level energies.
27.70.+q - .
© Società Italiana di Fisica, Springer-Verlag 2002