30MeV/u^(40)Ar+^(58,64)Ni、^(115)In反应中IMF的元素分布  

Element Distributions of Intermediate Mass Fragments Emitted in 30 MeV/u ^(40)Ar+^(58,64)Ni and ^(115)In Reactions

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

机构地区：[1]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6期512-517,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资助!KJ95T-03

摘　　要：在5°—140°范围内测量了30MeV／u40Ar束流轰击不同靶核（58Ni、64Ni、115In）时出射的中等质量碎片的元素分布．在20°—80°之间，观察到了原子序数大于弹核原子库数的出射碎片（Z＝3—24），发现中等质量碎片的微分截面在其原子库数从小于弹核原子库数向大于弹核原子库数变化过程中是连续变化的，该角区出就碎片的元素分布与弹核原子库数关系不大．对中能区核反应的过渡性质做了讨论，指出了探测阈对所测得的元素分布的影响，并讨论了元素分布的幂指数规律.The element distribuhons of intermediate mass fragments (IMF) emitted over an angular region of 5°-140° have been measured in the reachons of 30MeV/u 40Ar + 58, 64 Ni and 115 In. Within 20°- 80° range the IMFs with Z= 3-24 were observed. The IMF production cross section changes smoothly with its charge number,and the element distribuhon changes continuously when the IMF charge number increases across the charge number of the projectile. There is no strong dependence of the element distribution on the charge number of the projectile in this angular region.The transition nature of the reaction mechanism in the intermediate energy region and the power law of the IMF element distribution,as well as the dependence of element distributions on the threshold of the detectors were discussed.

关 键 词：中等质量碎片 元素分布 重离子碰撞 氩40 镍58 

分 类 号：O571.426[理学—粒子物理与原子核物理]