最优化方法应用于裂变核反应理论计算的研究  

Optimization Method Applied to Theoretical Calculation of Fission Nuclear Reaction

作　　者：田源[1] 续瑞瑞[1] 张玥 陶曦[1] 王记民[1] 金永利[1] 张智 孙小东 葛智刚[1] TIAN Yuan;XU Ruirui;ZHANG Yue;TAO Xi;WANG Jimin;JIN Yongli;ZHANG Zhi;SUN Xiaodong;GE Zhigang(China Nuclear Data Center,Key Laboratory of Nuclear Data,China Institute of Atomic Energy,Beijing 102413,China)

机构地区：[1]中国原子能科学研究院核数据重点实验室,中国核数据中心,北京102413

出　　处：《原子能科学技术》2022年第5期918-926,共9页Atomic Energy Science and Technology

摘　　要：中子诱发裂变核反应的反应机制十分复杂,需由光学模型、复合核模型等共同描述,因此需同时对大量参数进行调节才能正确描述裂变核反应数据。本文在FUNF裂变核反应模型基础上,利用先进的最优化方法MINUIT,结合MPI的并行计算方法,研究了MINUIT对裂变核反应调参的工作原理,并以中子诱发^(238)U的裂变核反应为例,验证了裂变核反应数据优化方法的可靠性。Nuclear data are fundamental data for nuclear energy,nuclear engineering,nuclear technology applications and nuclear science research,and have always received national attention.In particular,the importance of neutron-induced fission nuclear reaction data is unquestionable and the theoretical evaluation of nuclear data is required for a long period of time.The reaction mechanism of neutron induced fission reaction is very complicated and needs to be described by several different nuclear reaction models,such as optical potential model and compound nuclei model and so on.Nowadays,the most famous international nuclear reaction program systems are TALYS and EMPIRE.In China,the program FUNF is a fission nuclear reaction program system with our own independent intellectual property rights,which was developed by Prof.Zhang Jingshang of the China Nuclear Data Center.Each of these program systems need more than 40 parameters to be adjusted.Therefore,it is necessary to optimize a large number of parameters at the same time in order to correctly describe the nuclear fission reaction data.In this work,the FUNF program system was used to calculate the fission reaction data of neutron induced ^(238)U.The fast neutron reaction data of fissile materials with incident energy from about 1 keV up to 20 MeV were calculated by FUNF code.It consists of the spherical optical model,the Hauser-Feshbach model,and the angular momentum dependent exciton model to describe the emission from compound nucleus to the discrete levels of the residual nuclei in pre-equilibrium process,meanwhile equilibrium reaction process was described by the Hauser-Feshbach model with width fluctuation correction.Based on the FUNF nuclear fission reaction model,the parameters of the FUNF program system was adjusted by the advanced optimization method MINUIT.MINUIT is a numerical minimization software library in the Fortron by CERN staff Fred James in the 1970 s.Then,combined with the parallel calculation method of MPI(message passing interface),preliminary calcu

关 键 词：最优化方法MINUIT 裂变核 核反应截面 FUNF 并行化方法MPI 

分 类 号：TL32[核科学技术—核技术及应用]