Measurement of the U-238/U-235 fission cross section ratio at CSNS – Back-n WNS. (1st June 2020)

• Record Type: Journal Article
• Authors: Wen, Jie; Yang, Yiwei; Wen, Zhongwei; Liu, Rong; Liu, Xingyan; Han, Zijie; Chen, Qiping; Ren, Zhizhou; An, Qi; Bai, Huaiyong; Bao, Jie; Cao, Ping; Chen, Yonghao; Cheng, Pinjing; Cui, Zengqi; Fan, Ruirui; Feng, Changqing; Gu, Minhao; Guo, Fengqin; Han, Changcai; He, Guozhu; He, Yongcheng; He, Yuefeng; Huang, Hanxiong; Huang, Weiling; Huang, Xiru; Ji, Xiaolu; Ji, Xuyang; Jiang, Haoyu; Jiang, Wei; Jing, Hantao; Kang, Ling; Kang, Mingtao; Li, Bo; Li, Lun; Li, Qiang; Li, Xiao; Li, Yang; Li, Yang; Liu, Shubin; Luan, Guangyuan; Ma, Yinglin; Ning, Changjun; Qi, Binbin; Ren, Jie; Ruan, Xichao; Song, Zhaohui; Sun, Hong; Sun, Xiaoyang; Sun, Zhijia; Tan, Zhixin; Tang, Hongqing; Tang, Jingyu; Wang, Pengcheng; Wang, Qi; Wang, Taofeng; Wang, Yanfeng; Wang, Zhaohui; Wang, Zheng; Wu, Qingbiao; Wu, Xiaoguang; Wu, Xuan; Xie, Likun; Yi, Han; Yu, Li; Yu, Tao; Yu, Yongji; Zhang, Guohui; Zhang, Jing; Zhang, Linhao; Zhang, Liying; Zhang, Qingmin; Zhang, Qiwei; Zhang, Xianpeng; Zhang, Yuliang; Zhang, Zhiyong; Zhao, Yingtan; Zhou, Liang; Zhou, Zuying; Zhu, Danyang; Zhu, Kejun; Zhu, Peng;
• Is Part Of: Annals of nuclear energy. Volume 140(2020)
• Publication Date: 2020-06-01
• Subjects: U-238/U-235 fission cross section ratio -- CSNS – Back-n WNS -- Multi-cell fast fission ionization chamber -- Time-of-flight method; Nuclear energy -- Periodicals; Nuclear engineering -- Periodicals; 621.4805
• DOI: 10.1016/j.anucene.2019.107301
• Languages: English
• ISSNs: 0306-4549

Abstract

Highlights: Measured the 238U/235U fission cross section ratio in 1–20 MeV. The nonuniformity of the neutron beam profile was considered. Experimental uncertainties of 2.3%–3.6% in 1.4–20 MeV while 4.1%–11% in 1–1.4 MeV. Provide information and data support in relevant nuclear data evaluation. Abstract: Based on the China Spallation Neutron Source (CSNS) – Back-streaming white neutron source (Back-n WNS), the measurement of the U-238/U-235 fission cross section ratio in 1–20 MeV neutron energy region has been carried out by a multi-cell fast fission ionization chamber using the time-of-flight method. The measured resonance peaks of the 235 U(n, f) reaction are in good agreement with those of the ENDF/B-8.0 database. The measured six groups of the U-238/U-235 fission cross section ratios in 1–20 MeV neutron energy region agree with those of the ENDF/B-8.0 database in trend, and the average discrepancies between experiment and database are from 1.9% to 2.6%. The relative experimental uncertainties are 2.3%–3.6% (1.4–20 MeV), and the measured data agree with those of database within experimental uncertainties at most energy points. The measured U-238/U-235 fission cross section ratio could provide information and data support in relevant nuclear data evaluation.