Cross section measurement of neutron capture reaction based on back-streaming white neutron source at China spallation neutron source
Authors: Zhang Qi-Wei , Luan Guang-Yuan , Ren Jie , Ruan Xi-Chao , He Guo-Zhu , Bao Jie , Sun Qi , Huang Han-Xiong , Wang Zhao-Hui , Gu Min-Hao , Yu Tao , Xie Li-Kun , Chen Yong-Hao , An Qi , Bai Huai-Yong , Bao Yu , Cao Ping , Chen Hao-Lei , Chen Qi-Ping , Chen Yu-Kai , Chen Zhen , Cui Zeng-Qi , Fan Rui-Rui , Feng Chang-Qing , Gao Ke-Qing , Han Chang-Cai , Han Zi-Jie , He Yong-Cheng , Hong Yang , Huang Wei-Ling , Huang Xi-Ru , Ji Xiao-Lu , Ji Xu-Yang , Jiang Wei , Jiang Hao-Yu , Jiang Zhi-Jie , Jing Han-Tao , Kang Ling , Kang Ming-Tao , Li Bo , Li Chao , Li Jia-Wen , Li Lun , Li Qiang , Li Xiao , Li Yang , Liu Rong , Liu Shu-Bin , Liu Xing-Yan , Mu Qi-Li , Ning Chang-Jun , Qi Bin-Bin , Ren Zhi-Zhou , Song Ying-Peng , Song Zhao-Hui , Sun Hong , Sun Kang , Sun Xiao-Yang , Sun Zhi-Jia , Tan Zhi-Xin , Tang Hong-Qing , Tang Jing-Yu , Tang Xin-Yi , Tian Bin-Bin , Wang Li-Jiao , Wang Peng-Cheng , Wang Qi , Wang Tao-Feng , Wen Jie , Wen Zhong-Wei , Wu Qing-Biao , Wu Xiao-Guang , Wu Xuan , Yang Yi-Wei , Yi Han , Yu Li , Yu Yong-Ji , Zhang Guo-Hui , Zhang Lin-Hao , Zhang Xian-Peng , Zhang Yu-Liang , Zhang Zhi-Yong , Zhao Yu-Bin , Zhou Lu-Ping , Zhou Zu-Ying , Zhu Dan-Yang , Zhu Ke-Jun , Zhu Peng , Zhu Xing-Hua ,   Key Laboratory of Nuclear Data, China Institute of Atomic Energy, Beijing 102413, China,   Institute of High Energy Physics, Chinese Academy of Sciences (CAS), Beijing 100049, China,   Spallation Neutron Source Science Center, Dongguan 523803, China,   State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, China,   Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China,   State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871, China,   Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621900, China,   Northwest Institute of Nuclear Technology, Xi’an 710024, China,   University of Chinese Academy of Sciences, Beijing 100049, China,   Department of Engineering and Applied Physics, University of Science and Technology of China, Hefei 230026, China,   School of Physics, Beihang University, Beijing 100083, China,   Huaneng Shandong Shidao Bay Nuclear Power Co.Ltd, Rongcheng 264312, China
Published: August 2021

The data of neutron capture cross section are very important for the research of nuclear astrophysics, advanced nuclear energy development. Owing to the limitation of neutron source and detector, the experimental data of neutron capture cross section in an energy range of 1 eV–10 keV were almost blank in China. The first Chinese gamma-ray total absorption facility has been constructed in the key laboratory of nuclear data at China institute of atomic energy, which consists of 40 BaF<sub>2</sub> detector units. The BaF<sub>2</sub> crystal shell with a thickness of 15 cm and an inner radius of 10 cm covers 95.2% of the solid angle. On-line measurement method of neutron capture reaction cross section is established on the back-streaming white neutron source of China spallation neutron source by using the upgraded facility. The cross section of <sup>197</sup>Au neutron capture reaction is measured for the first time under the experimental condition of irregular 30 mm neutron beam spot. The measured position of resonance peak is well consistent with the relevant data of ENDF evaluation database, which verifies the reliability of the measurement device and measurement technology, and thus laying the foundation for the acquisition of high precision cross section in future.