双奇核^(172)Re高自旋态转动带结构实验研究  

Experimental Study of High-Spin Band Structures in Odd-Odd 172Re

作　　者：张玉虎[1] M.Oshima Y.Toh 周小红[1] M.Koizimi A.Osa A.Kimura Y.Hatsukawa T.Morikawa M.NakamuraDepartment of Physics Kyushu University Fukuoka Japan M.SugawaraChiba Institute of Technology Narashino Chiba 275-0023 Japan H.Kusakari T.Komatsubara K.Furuno 

机构地区：[1]中国科学院近代物理研究所,兰州730000 [2]Japan Atomic Energy Research Institute [3]Department of Physics [4]Chiba University [5]Institute of Physics and Tandem Accelerator Center

出　　处：《高能物理与核物理》2003年第7期574-580,共7页High Energy Physics and Nuclear Physics

基　　金：国家杰出青年科学基金 ( 10 0 2 5 5 2 5 ) ;国家自然科学基金 ( 10 0 5 0 12 );国家重点基础研究发展规划 (TG2 0 0 0 0 7740 0 );中国科学院资助~~

摘　　要：利用重离子熔合蒸发反应 14 9Sm (2 7Al,4nγ) 172 Re布居了形变双奇核 172 Re的高自旋态 ,用 12套带有BGO反康普顿抑制的高纯锗探测器阵列进行了在束γ实验测量 ,首次建立了形变双奇核172 Re由 3个转动带构成的高自旋态能级纲图 .研究和讨论了 3个转动带的结构特征 ,基于已有的高自旋态核结构知识并通过系统学比较和分析指出它们的准粒子组态分别为πh11 2 νi13 2 ,πh9 2 νi13 2 和π1 2 -[5 41] ν1 2 -[5 2 1].发现前两个转动带在自旋小于 18.5时其转动能级呈现反常的旋称劈裂 .High-spin states in odd-odd 172Re have been investigated via the 149Sm( 27Al,4nγ) 172Re reaction through excitation functions, X-γ and γ-γ coincidence measurements. A level scheme consisting of three rotational bands has been identified for the first time,extending the high-spin studies of A≈170 odd-odd nuclei to the currently lightest rhenium isotope. The three bands have been assigned to be built on the πh 11/2νi 13/2,πh 9/2νi 13/2 and π1/2-ν1/2- configurations according to their rotational properties in quasiparticle alignments, signature splitting, in-band B(M1)/B(E2) ratios, level spacing systematics, band crossing frequencies, as well as the existing knowledge in neighboring nuclei. Low-spin signature inversion has been confirmed in the first two bands due to observation of signature crossing at high-spin states.

关 键 词：高自旋态 原子核 形变双奇核 ^172Re 转动带 结构特征 实验研究 铼 在束Γ谱学 能级纲图 旋称劈裂 

分 类 号：O571.2[理学—粒子物理与原子核物理]