Determination of thorium fission rate based on I-135 in thorium oxide cylinder bombarded by D-T fusion neutrons

作者：Zheng, Lei; Yang, Yiwei; Liu, Rong^*; Liu, Zhujun; Wang, Mei; Jiang, Li; Wen, Zhongwei; Wang, Kan; Liu, Xingyan

来源：Annals of Nuclear Energy, 2018, 119: 264-270.

DOI：10.1016/j.anucene.2018.05.012

• Thorium fission rate
• I-135
• Activation method
• MCNP simulation
• D-T fusion neutrons
• Thorium oxide cylinder

Aiming at developing the activation method and provide reference for the validation of thorium fission parameters, a dedicated integral experiment was carried out in a thorium oxide cylinder bombard by D-T fusion neutrons. Thorium fission rate in the axial direction of the cylinder was determined by detecting the 1260.409 keV gamma emitted from fission product 1351, with experimental uncertainties of 6.2%. MCNP calculations employing ENDF/B-V11.0, ENDF/B-V11.1, JENDL-4.0, CENDL-3.1 library data were in good agreement with measured thorium fission rates within experimental uncertainties. The agreement of measured reaction rates of monitors with the calculations on the whole demonstrated the reliability of this experiment in some degree, and could provide reference for the analyses of thorium fission rates. Neutron spectra and the contribution of neutrons in each sub-energy range to thorium fission rate were also analyzed. The activation method to determine thorium fission rate was developed and the data obtained in this work could provide reference for the validation of thorium fission parameters.

• 出版日期2018-9
• 单位中国工程物理研究院核物理与化学研究所; 中国工程物理研究院; 清华大学