Cross section measurement for the ^(232)Th(n,f)reaction in the 4.50−5.40 MeV region using a time projection chamber  

作　　者：Haofan Bai Han Yi Yankun Sun Yiwei Hu Jie Liu Zepeng Wu Cong Xia Wenkai Ren Wentian Cao Tieshuan Fan Guohui Zhang Ruirui Fan Yang Li Wei Jiang Yonghao Chen You Lv Changjun Ning Weihua Jia Zhiyong Zhang Haolei Chen Zhen Chen Maoyuan Zhao Changqing Feng Shubin Liu 白浩帆;易晗;孙艳坤;胡益伟;刘杰;邬泽鹏;夏聪;任文凯;曹文田;樊铁栓;张国辉;樊睿瑞;李样;蒋伟;陈永浩;吕游;宁常军;贾伟华;张志永;陈昊磊;陈朕;赵懋源;封常青;刘树彬(State Key Laboratory of Nuclear Physics and Technology,Institute of Heavy Ion Physics,Peking University,Beijing 100871,China;Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China;Spallation Neutron Source Science Center,Dongguan 523803,China;National Key Laboratory of Intense Pulsed Radiation Simulation and Effect,Northwest Institute of Nuclear Technology,Xi'an 710024,China;Department of Nuclear Science and Technology,School of Energy and Power Engineering,Xi’an Jiaotong University,Xi’an 710049,China;State Key Laboratory of Particle Detection and Electronics,University of Science and Technology of China,Hefei 230026,China;Department of Modern Physics,University of Science and Technology of China,Hefei 230026,China)

机构地区：[1]State Key Laboratory of Nuclear Physics and Technology,Institute of Heavy Ion Physics,Peking University,Beijing 100871,China [2]Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China [3]Spallation Neutron Source Science Center,Dongguan 523803,China [4]National Key Laboratory of Intense Pulsed Radiation Simulation and Effect,Northwest Institute of Nuclear Technology,Xi'an 710024,China [5]Department of Nuclear Science and Technology,School of Energy and Power Engineering,Xi’an Jiaotong University,Xi’an 710049,China [6]State Key Laboratory of Particle Detection and Electronics,University of Science and Technology of China,Hefei 230026,China [7]Department of Modern Physics,University of Science and Technology of China,Hefei 230026,China

出　　处：《Chinese Physics C》2024年第10期157-167,共11页中国物理C（英文版）

基　　金：Supported by the National Natural Science Foundation of China(12075008);the Key Laboratory of Nuclear Data foundation(6142A08200103);the Basic and Applied Basic Research Foundation of Guangdong Province,China(2021B1515120027);the State Key Laboratory of Nuclear Physics and Technology,Peking University(NPT2021KFJ57)。

摘　　要：Accurate cross sections of neutron induced fission reactions are required in the design of advanced nuclear systems and the development of fission theory.Time projection chambers(TPCs),with their track reconstruction and particle identification capabilities,are considered the best detectors for high-precision fission cross section measurements.The TPC developed by the back-streaming white neutron source(Back-n)team of the China Spallation Neutron Source(CSNS)was used as the fission fragment detector in measurements.In this study,the cross sections of the ^(232)Th(n,f)reaction at five neutron energies in the 4.50−5.40 MeV region were measured.The fission fragments and α particles were well identified using our TPC,which led to a higher detection efficiency of the fission fragments and smaller uncertainty of the measured cross sections.Ours is the first measurement of the ^(232)Th(n,f)reaction using a TPC for the detection of fission fragments.With uncertainties less than 5%,our cross sections are consistent with the data in different evaluation libraries,including JENDL-4.0,ROSFOND-2010,CENDL-3.2,ENDF/B-VⅢ.0,and BROND-3.1,whose uncertainties can be reduced after future improvement of the measurement.

关 键 词：^(232)Th(n f)fission cross section time projection chamber(TPC) ^(232)Th 

分 类 号：O571.43[理学—粒子物理与原子核物理]