摘要
In this study,we investigate the robustness of pair structures for nuclear yrast states,that is,whether the structures of relevant collective pairs as building blocks of different yrast states are the same.We focus on deformed and transitional nuclei and study the yrast states of^(28)Si,^(50)Cr,and^(132)Xe,whose experimental R_(4/2)values are 2.60,2.40,and 2.16,respectively,using the nucleon-pair approximation(NPA)and shell-model effective interactions.For each yrast state,we consider optimized pair structures to be those providing the energy minimum for this state.To find the minimum,many full NPA calculations are performed with varying pair structures,and the numerical optimization procedure of the conjugate gradient method is implemented.Our results suggest that optimized pair structures remain the same for all states within a rotational band of a deformed nucleus.Our results also suggest that after backbending,that is,changing of the intrinsic state,the structure of the S pair,which is essential to build the monopole pairing correlation,remains approximately unchanged,whereas the structures of the non-S pairs,which are essential to build the quadrupole correlation,change significantly.
作者
潘一飞
程奕源
路毅
姜慧
周先荣
赵玉民
Yi-Fei Pan;Yi-Yuan Cheng;Yi Lu;Hui Jiang;Xian-Rong Zhou;Yu-Min Zhao(Department of Physics,East China Normal University,Shanghai 200241,China;College of Physics and Engineering,Qufu Normal University,Qufu 273165,China;School of Science,Shanghai Maritime University,Shanghai 201306,China;School of Physics and Astronomy,Shanghai Jiao Tong University,Shanghai 200240,China;IFSA Collaborative Innovation Center,Shanghai Jiao Tong University,Shanghai 200240,China)
基金
Supported by the National Natural Science Foundation of China(11875134,11875188,12175071,11975151,11961141003)
the Shanghai Key Laboratory of Particle Physics and Cosmology(21DZ2271500-2)。