30MeV/u^(40)Ar+^(58,64)Ni和^(115)In反应中中等质量碎片的角分布  

The Angular Distributions of intermediate Mass Fragments Emittsd in 30 MeV/u ^(40)Ar + ^(58,64)Ni and ^(115)In Reactions

作　　者：苟全补[1] 诸永泰[2] 徐瑚珊[2] 魏志勇[2] 卢俊[2] 张玉虎[2] 王琦[2] 李松林[2] 吴钟立[2] 

机构地区：[1]兰州大学现代物理系 [2]中国科学院近代物理研究所,兰州730000

出　　处：《高能物理与核物理》1999年第4期328-333,共6页High Energy Physics and Nuclear Physics

基　　金：国家自然科学基金!19235012;中国科学院九五重大项目

摘　　要：在5°—140°范围内测量了30MeV／u(40)Ar束流轰击不同靶核（(58)Ni、(64)Ni、(115)In）后出射的中等质量碎片（IMF，Z＝3—19）的角分布．用指数分布函数dσ／dΩ＝N·exp（－θ／α）对出射碎片角分布分角区做了拟合．对3个反应系统分别提取出与相互作用时间有关的衰减因子α和与发射源强度有关的物理量N,讨论了α与N在不同角区与反应系统和出射IMF电荷数的关系．考察了角分布与同位旋自由度和反应系统对称性的关系．The angular distributions of intermediate mass fragments with Z=3-19 emitted in 30 MeV/u 40Ar + 58,64Ni and 115In reactions over an angular range of 5°140°have been measured.Exponential distribution function: dσ/dΩ=N·exp(-θ/a) was used tO fit the measured angular distributions.We have extracted the decay factor a that can be connected with the interaction time τ, and the factor N that is related to the intensity of the emission source.The relationships of a(Z) with Z and N(Z) with Z for different reaction systems and different angular ranges have been discussed. The dependence of angular distributions on isospin and the symmetry of reaction system have also been discussed. Received 25 May 1998 * Supported by the National Natural Science Foundation of China(19235012) and the Chinese Academy of Sciences1)Ph. D student of IMP, being on his job as a lecturer of Modern Physics Department of hanzhou University

关 键 词：中等质量碎片 角分布 氩 镍 铟 重离子反应 

分 类 号：O571.426[理学—粒子物理与原子核物理]