超形变核^(149)Tb中的旋称伙伴带  

Signature Partners in Superdeformed ^(149) Tb

作　　者：吴崇试[1,2] 

机构地区：[1]兰州重离子加速器国家实验室原子核理论中心 [2]北京大学物理系北京100871

出　　处：《高能物理与核物理》2001年第3期205-211,共7页High Energy Physics and Nuclear Physics

基　　金：国家自然科学基金资助! (196772 0 3)&&

摘　　要：系统分析了14 9Tb中的 5条超形变带 .在对跃迁能量进行光滑化处理后 ,采用ab拟合或改进的ab拟合 ,确切地指定了它们的自旋值 .其 2 ,4和 3,5两带都分别构成旋称伙伴带 .根据它们的脱耦合常数值 ,指认了14 9Tb费米面附近相应的Ω =1/Five superdeformed bands observed in 149 \ Tb were investigated comprehensively. A large amplitude fluctuation in the observed transition energies and hence in the extracted dynamic moments of inertia was found in most of these bands. The smoothed transition energies were deduced by removing the fluctuation. The spins of these bands were assigned conclusively by the ab fitting and/or its modification. Two pairs of superdeformed bands in 149 \ Tb, i.e. bands 3,5 and bands 2,4,were proposed to be signature partners. The exit spins are 59/2 and 61/2 for the former pair,and 49/2 and 63/2 for the latter pair. These values are different by one unit from those given from a comparison with 150 \ Tb (1). In fact,the spins of 150 \ Tb(1), which have not been determined experimentally,are different by different theoretical approaches of assignment. The de coupling constants were extracted from the modified ab fitting. Responsible Ω =1/2 orbit in the vicinity of the Fermi surface of 149 \ Tb seems to be ν[640]↑ for bands 2 and 4,and π[301]↓ for bands 3 and 5. The exit spin of band 1 was assigned as 53/2 or 55/2,which may be picked out from the observation of its signature partner. Good correspondence between these bands(especially bands 2,4 and 5) and their identical bands was obtained.

关 键 词：超形变带 原子核转动惯量 ab拟合 自旋值 旋称伙伴带 149Tb 粒子态 跃迁能量 

分 类 号：O571[理学—粒子物理与原子核物理]