25MeV/u^6He在~9Be靶上引起的双中子转移  

Two-Neutron Transfer Induced by ~6He Nuclear Beam at 25MeV/u on a ~9Be Target

作　　者：葛愉成[1] 叶沿林[1] 郑涛[1] 王全进[1] 李智焕[1] 李湘庆[1] 江栋兴[1] A.Ozawa Y.Yamaguchi C.Wu R.Kanungo D.Fang I.Tanihata 

机构地区：[1]北京大学技术物理系,教育部重离子物理开放实验室,北京100871 [2]RIKEN,2-1 Hirosawa,Wako,Saitam 351-0198,Japan

出　　处：《高能物理与核物理》2004年第3期262-267,共6页High Energy Physics and Nuclear Physics

基　　金：国家重点基础研究发展规划 (G2 0 0 0 0 7740 0 )资助~~

摘　　要：报道了经仔细设计的 15 0MeV6He +9Be实验 ,并在质心系大角度处测量 10 Be和 11Be同位素产物的实验数据 .鉴别得到相应于单中子转移的 371个 10 Be事件 ,同时观测到了相应于双中子转移的 5个 11Be事件 .由此得到相应微分截面分别为 (0 .11± 0 .0 2 )mb sr(θcm≈ 137.4°)和 (1.0± 0 .7)μb sr(θcm≈ 133.4°) ,结果表明在所研究的反应体系中 ,单中子转移截面要比双中子转移截面约大10 0倍 .在 6He由 5He n和α 2n组成的集团模型下 ,利用零力程扭曲波玻恩近似 (DWBA)的计算程序 ,在数量级上重现了单。n-and 2n-transfer reaction products 10Be and 11Be at large c.m. angles were measued in a specially designed set-up for the bombardment of 9Be by 6He at 150MeV. In total 371 10Be and 5 11Be events, corresponding to 1n-and 2n-transfer respectively were identified. The experimental differential cross-sections obtained are 0.11±0.02mb/sr(θ cm≈137.4°) and 1.0±0.7μb/sr(θ cm≈133.4°) for 1n- and 2n-transfer, respectively. Such results indicate that the differential cross-section of 1n-transfer is about 100 times higher than that of 2n-transfer at large c.m. angle in the reaction studied. Calculation using zero range Distorted Wave Born Approximation(DWBA) for 6He under 5He-n and α-2n two-cluster models are performed and discussed.

关 键 词：放射性束物理 双中子转移反应 微分截面 零力程扭曲波玻恩近似 铍靶 双中子转移 

分 类 号：O571.5[理学—粒子物理与原子核物理]