N=28附近奇A核Co同位素的晕态研究  

The Yrast State Investigations of Odd-A Co Isotopes around N=28

作　　者：陈铎 郭瑞 王恒毅 金华[3] 李剑[1] CHEN Duo;GUO Rui;WANG Hengyi;JIN Hua;LI Jian(College of Physics,Jilin University,Changchun 130012,China;School of Physics,Beihang University,Beijing 100083,China;School of Arts and Sciences,Shanghai Dianji University,Shanghai 201306,China)

机构地区：[1]吉林大学物理学院,长春130012 [2]北京航空航天大学物理学院,北京100083 [3]上海电机学院文理学院,上海201306

出　　处：《原子核物理评论》2024年第1期184-190,共7页Nuclear Physics Review

基　　金：吉林省自然科学基金项目(20220101017JC);国家自然科学基金资助项目(11675063)。

摘　　要：奇A核53-65Co负宇称晕态能级结构的系统性比较表明,^(55)Co存在能级9/2-与11/2^(-)反转,且^(53,57)Co可能存在较强的集体效应。基于GXPF1A有效相互作用的壳模型计算较好地再现这些核的晕态能级,及相应的磁矩和电四极矩实验值。壳模型计算结果展示^(53-65)Co基态7/2^(-)波函数中质子主要组态成分均为π(1f_(7/2))7。^(55)Co中激发态9/2^(-)与11/2^(-)中1f_(7/2)质子激发和1f_(7/2)中子激发之间存在竞争,从而导致两能级反转。此外,利用Constrained Hartree-Fock(CHF)方法研究了^(53,55,57)Co四极形变特征,结合壳模型计算得到的平均占据数和组态,分析了^(55)Co激发态能量相较于其他Co同位素更高的原因。A systematic comparison of the negative parity yrast states'energy level structures indicates a level inversion between the9/2-and the 11/2-in ^(55)Co,and suggests that ^(33)Co and ^(57)Co might exhibit strong collective effects.Shell model calculations based on the GXPF1A effective interaction accurately reproduce yrast state halo state energy levels of these nuclei,as well as the corresponding experimental magnetic moments and electric quadrupole moments.The shell model results show that the dominant component of proton configuration for the ground state 7/2-in ^(53-65)Co is(1f/2).The excited states 9/2-and 11/2-in ^(55)Co involve a competition between 1f/2 proton excitation and 1fu/2 neutron excitation,leading to a possible level inversion between the these states.Moreover,by using the Constrained Hartree-Fock(CHF)method to study the quadrupole deformation characteristics of ^(53)Co,^(55)Co and 57co,and combining the average occupancy numbers and configurations obtained from shell model calculations,the reasons for higher the excited state energies of ^(55)Co compared to other Co isotopes were analyzed.

关 键 词：CO 壳模型 晕态 基态自旋 原子核形变 

分 类 号：O571.6[理学—粒子物理与原子核物理]