25MeV/u　^(40)Ar+^(209)Bi裂变反应研究  

Investigation of Fission Properties in the Reaction 25MeV/u ^(40)Ar + ^(209)Bi

作　　者：郑纪文[1] 邬恩九[1] 肖志刚[1] 张纯[1] 尹淑芝[1] 王素芳[1] 靳根明[1] 谭继廉[1] 金卫阳 宋明涛[1] 李祖玉[1] 吴和宇[1] 贺智勇 殷旭[1] 朋兴平[1] 江栋兴[2] 钱兴[2] 

机构地区：[1]中国科学院近代物理研究所,兰州730000 [2]北京大学技术物理系,北京100871

出　　处：《高能物理与核物理》1999年第5期409-416,共8页High Energy Physics and Nuclear Physics

基　　金：国家自然科学基金!19235011

摘　　要：实验对25MeV／u^(40)Ar＋^(209)Bi体系的裂变反应，利用线性动量转移的分窗选择不同的激发能，研究裂变动能分布和质量分布与热核初始激发能的关系．实验证实激发能小于380MeV时裂变总动能分布与低激发能复合核相似．激发能大于380MeV时，最可几动能呈现出随激发增加而增加，并出现高能非对称性，而且质量分布宽度随激发能增加而迅速增大．The distribution properties of the total fission kinehc energy and of themass of fission fragments at different initial excitation energies of hot nuclei in thereaction 25MeV / u ^(40)Ar +^(209)Bi are investigated. The initial excitation energies areobtained according to the linear momentum transfer. The experimental results showthat the fission kinetic energy distribution is similar to the case of compound nucleiwith lower excitation energy when the initial excitation energy of hot nuclei is below380MeV. While the inihal excitation energy is above 380MeV, the most probablevalue of fission kinehc energy increases with the inihal excitahon energy. The fissionenergy spectra become asymmetric due to an enhancement of the yield at higherkinehc energies, and the width of mass distribution increases rapidly.

关 键 词：裂变 碎片总功能 激发能 中能 重离子 氩40 

分 类 号：O571.43[理学—粒子物理与原子核物理]