^(230)Ac的β延发裂变  

β-DELAYED FISSION FROM ^(230)Ac

作　　者：杨维凡[1] 袁双贵[1] 徐岩冰[1] 熊兵[1] 潘强岩[1] 何建军[1] 肖永厚[1] 李英俊[1] 

机构地区：[1]中国科学院近代物理研究所,甘肃兰州730000

出　　处：《核化学与放射化学》2002年第1期38-41,共4页Journal of Nuclear and Radiochemistry

基　　金：国家自然科学基金资助项目 (19775 0 5 5 ;10 0 75 0 63 );中国科学院基金资助项目 (KJ95T 0 3 )

摘　　要：用 6 0MeV/u18O离子轰击ThO2 ,通过多核子转移和靶的耗散碎裂反应产生2 3 0 Ra。利用放射化学分离技术 ,将镭与钍及其它反应产物分离并制备成薄镭源。该源对云母裂变径迹探测器暴光 ,用高纯锗探测器测量镭源的γ活度 ;用氢氟酸溶液对云母箔进行蚀刻 ,使用光学显微镜观测云母箔中的裂变径迹。首次观测到了可能来自2 3 0 Acβ延发裂变的两个事件 ,获得它的 β延发裂变几率为 (1 19± 0 85 )× 10 -8。ThO 2 is irradiated with 60 MeV/u 18 O beams. 230 Ra is produced via the multi nucleon transfer and dissipative fragmentation reactions of the target. 230 Ra is radio chemically separated from ThO 2 and the other reaction products. The thin Ra sources are prepared. The mica fission track detectors are exposed to the Ra sources. γ Rays of Ra decay in the sources are measured by a HPGe detector. The mica foil is etched in HF solution. The etched mica foil is scanned with an optical microscope. The fission tracks that should come from β delayed fission of 230 Ac are observed. The β delayed fission probability of 230 Ac is determined to be (1.19±0.85)×10 -8 .

关 键 词：β延发裂变 化学分离 裂变几率 原子核衰变 锕230 镭 

分 类 号：O571.322[理学—粒子物理与原子核物理] O614.351[理学—物理]