A study of 239 Pu production rate in a water cooled natural uranium blanket mock-up of a fusion–fission hybrid reactor

• Published in: Nuclear fusion 2016-03, Vol.56 (3), p.36019
• Main Authors: Feng, Song, Liu, Rong, Lu, Xinxin, Yang, Yiwei, Xu, Kun, Wang, Mei, Zhu, Tonghua, Jiang, Li, Qin, Jianguo, Jiang, Jieqiong, Han, Zijie, Lai, Caifeng, Wen, Zhongwei
• Format: Article
• Language: English
• ISSN: 0029-5515; 1741-4326
• DOI: 10.1088/0029-5515/56/3/036019

The 239 Pu production rate is important data in neutronics design for a natural uranium blanket of a fusion–fission hybrid reactor, and the accuracy and reliability should be validated by integral experiments. The distribution of 239 Pu production rates in a subcritical natural uranium blanket mock-up was obtained for the first time with a D-T neutron generator by using an activation technique. Natural uranium foils were placed in different spatial locations of the mock-up, the counts of 277.6 keV γ -rays emitted from 239 Np generated by 238 U capture reaction were measured by an HPGe γ spectrometer, and the self-absorption of natural uranium foils was corrected. The experiment was analyzed using the Super Monte Carlo neutron transport code SuperMC2.0 with recent nuclear data of 238 U from the ENDF/B-VII.0, ENDF/B-VII.1, JENDL-4.0u2, JEFF-3.2 and CENDL-3.1 libraries. Calculation results with the JEFF-3.2 library agree with the experimental ones best, and they agree within the experimental uncertainty in general with the average ratios of calculation results to experimental results (C/E) in the range of 0.93 to 1.01.