Lifetimes of High Spin States in an Odd-Proton Nucleus 129Cs  

作　　者：王烈林 竺礼华 陆景彬 吴晓光 李广生 郝昕 郑云 贺创业 汪雷 李雪琴 刘颖 潘波 赵延新 李忠宇 丁怀博 

机构地区：[1]Department of Physics, Jilin University, Changchun 130023 [2]China Institute of Atomic Energy, Beijing 102413 [3]Faculty of Science, Shenzhen University, Shenzhen 518060 [4]School of Physics, Peking University, Beijing 100871 [5]Department of Physics, Tsinghua University, Beijing 100084

出　　处：《Chinese Physics Letters》2010年第2期54-57,共4页中国物理快报（英文版）

基　　金：Partially supported by the National Basic Research Development Program of China under Grant No 2007CB815000, and the National Natural Science Foundation of China under Grant Nos 10775184, 10675171, 10575133, 10575092 and 10375092.

摘　　要：Lifetimes of high spin states in 129Cs axe measured using the Doppler shift attenuation method. The high spin states of 129 Cs axe populated following the fusion evaporation reaction 124 Sn（UB, 6n）129 Cs at a beam energy of 65 MeV. The reduced transition probabilities B（E2） and the transition quadrupole moments Qt in the negativeand positive-paxity bands are deduced. The experimental results indicate that the Qt values of the negative parity band are smaller than those of the positive parity bands, probably due to different γ-deformation driving effects of different proton orbitals. The Qt values exhibit a considerable increase near the band crossing region in these bands. This behavior demonstrates that nuclear shape changing results from the neutron or proton alignments. The signature splitting of the πh11/2 and πg7/2 bands shows the opposite changing trend after backbending due to the h11~2 neutron and h11/2 proton alignments, respectively.Lifetimes of high spin states in 129Cs axe measured using the Doppler shift attenuation method. The high spin states of 129 Cs axe populated following the fusion evaporation reaction 124 Sn（UB, 6n）129 Cs at a beam energy of 65 MeV. The reduced transition probabilities B（E2） and the transition quadrupole moments Qt in the negativeand positive-paxity bands are deduced. The experimental results indicate that the Qt values of the negative parity band are smaller than those of the positive parity bands, probably due to different γ-deformation driving effects of different proton orbitals. The Qt values exhibit a considerable increase near the band crossing region in these bands. This behavior demonstrates that nuclear shape changing results from the neutron or proton alignments. The signature splitting of the πh11/2 and πg7/2 bands shows the opposite changing trend after backbending due to the h11~2 neutron and h11/2 proton alignments, respectively.

分 类 号：O571.22[理学—粒子物理与原子核物理] O571.2[理学—物理]