0.57、1.0和1.5MeV中子诱发^(235)U裂变的^(99)Mo产额绝对测量  

Absolute Measurement of ^(99)Mo Fission Yields of ^(235)U Induced by 0.57,1.0 and 1.5 MeV Neutrons

作　　者：冯晶[1] 鲍杰[1] 杨毅[1] 刘世龙[1] 张春利[1] 杨洋[1] 刘永辉[1] 

机构地区：[1]中国原子能科学研究院核物理研究所,北京102413

出　　处：《原子能科学技术》2013年第9期1473-1478,共6页Atomic Energy Science and Technology

基　　金：国防基础科研计划资助项目(B0120110034)

摘　　要：用HPGe γ能谱法绝对测量了0.57、1.0和1.5MeV中子诱发235 U裂变产物99 Mo的产额,使用双裂变室测量了样品辐照过程中的裂变率,应用MCNPⅣB模拟了铀样品中的中子能谱,并讨论了非主中子的各种来源对产额数据的影响。得到99 Mo在0.57、1.0和1.5 MeV的产额分别为6.61%、6.62%和6.28%。本工作与美国阿贡实验室的结果有15%以上的相对偏差,主要是由引用的衰变数据不同引起。对阿贡实验室数据进行校正后,本工作与阿贡实验室数据的相对偏差处于实验不确定度范围内。The chain yields of fission product 99Mo were determined for the fission of 2asu induced by 0.57, 1.0 and 1.5 MeV neutrons. Absolute fission rate was monitored with a double-fission chamber. Fission product activities were measured by HPGe 9＇-ray spectrometry. MCNP IV B was applied to simulate neutron spectrum in uranium samples, and the effects of all kinds of secondary neutrons on fission yield data were discussed. The fission yields of 99Mo for 0.57, 1.0 and 1.5 MeV neutrons are 6.61%, 6.62% and 6.28%, respectively. The yield data were compared with those of ANL. Our results are in agreement with those of ANL within the scope of experimental uncertainties after necessary corrections.

关 键 词：裂变产额99_Mo 235_U r 能谱法 

分 类 号：O571.43[理学—粒子物理与原子核物理]