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Conference Spotlight
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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Japan gets new U for enrichment as global power and fuel plans grow
President Trump is in Japan today, with a visit with new Prime Minister Sanae Takaichi on the agenda. Takaichi, who took office just last week as Japan’s first female prime minister, has already spoken in favor of nuclear energy and of accelerating the restart of Japan’s long-shuttered power reactors, as Reuters and others have reported. Much of the uranium to power those reactors will be enriched at Japan’s lone enrichment facility—part of Japan Nuclear Fuel Ltd.’s Rokkasho fuel complex—which accepted its first delivery of fresh uranium hexafluoride (UF₆) in 11 years earlier this month.
A. Gibello, F. V. Orestano, F. Pistella, E. Santandrea
Nuclear Science and Engineering | Volume 40 | Number 1 | April 1970 | Pages 51-72
Technical Paper | doi.org/10.13182/NSE70-A18879
Articles are hosted by Taylor and Francis Online.
Spectral indexes have been measured in homogeneous systems (solutions of europium and boron). The measured values have been compared with the results of spectra calculations and, independently, have been utilized for a correlation method devised to deduce the reaction rates which are undetectable directly. The reliability of the THERMOS code for spectra calculations in such systems has been shown. A satisfactory test of the correlation method has been performed. The adequacy of the cross-section sets available in the literature has been shown for the detectors 197Au, 63Cu, 55Mn, 176Lu, 239Pu, and 235U. The sets available for 151Eu and 175Lu are not satisfactory: new evaluations have been carried out by properly utilizing measurements reported in the literature and/or new measurements performed for this purpose in a known spectrum. When using the new sets, the agreement between calculated and experimental spectral indexes in the absorber solutions is significantly improved. When reliable cross sections are available for the detectors, the correlation method can be considered a powerful tool for the evaluation of an unknown reaction rate: for instance the 239Pu absorption rate in the solutions is evaluated by means of the measured activation rates without introducing uncertainties due to the correlation procedure itself.
