中子入射钆核反应的理论计算  

Theoretical calculation of n+Gd nuclear reaction

作　　者：张开强[1] 张正军[1] 胡继峰[2] 陈金根[2] 

机构地区：[1]西北大学物理学系,西安710069 [2]中国科学院上海应用物理研究所嘉定园区,上海201800

出　　处：《核技术》2013年第9期56-62,共7页Nuclear Techniques

基　　金：中国科学院战略性先导科技专项钍基熔盐堆资助

摘　　要：在光学模型的假设下,以中子与钆核反应的总截面、弹性散射角分布等实验数据作为基础,使用APMN程序寻求到一组描述这个反应过程的光学势参数。在扭曲波波恩近似理论下,应用DPPM程序计算核反应过程的直接非弹性散射部分。应用以上结果,使用基于球形光学势理论、统一的Hauser-Feshbach理论的UNF程序,计算核反应过程中的各种截面,中子数据以及各种反应道的出射道的截面。在计算完各种数据后,与实验数据比较并给出没有实验数据区域的理论结果。Background： Nuclear energy has the advantages of efficient, clean and reserves. Our country has launched a new type of nuclear reactor： thorium-based molten salt reactor nuclear system project since 2011. Purpose： We want to make sure the data of the nuclear reaction of n＋Gd, including the total cross section, elastic scattering angular distribution, elastic scattering cross section, direct inelastic scattering cross section, absorption cross section, various of reaction channels cross section, double differential cross section of neutrons emitted, etc. The experimental data was compared and the theoretical results of nuclear reaction of n＋Gd were given. Methods： First, the optical model is used to describe the nuclear reaction process, the reflection and refraction of light entering into a different media is used to describe the scattering and absorption of phenomenon of nuclear reaction, and a set of optical potential parameters is applied to describe the reaction. The total cross section, elastic scattering cross section, elastic scattering angular distributions and some other data were calculated based on the experimental data and this set of optical potential parameters. Then the direct inelastic scattering cross section was calculated on the basis of distorted wave Born approximation and optical potential parameters. Finally, based on the above calculation results and the theoretical of the unified Hauser-Feshbach and exciton model, the UNF program was used for calculating the variation of cross sections data and kinds of reaction channels. Results： The calculating results agree with the experimental data very well and can reflect the process of nuclear reaction approximately. Conclusions： The calculating results based on this set of optical potential parameters seem credible, and the process of nuclear reaction using the optical model assumption is reasonable. Based on the calculation of n＋Gd, the Gd element can be used as a nuclear reactor control rod material, and nuclear reaction rate

关 键 词：光学模型 Hauser-Feshbach理论 总截面 弹性散射角分布 

分 类 号：TL361[核科学技术—核技术及应用]