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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.
Richard E. Faw
Nuclear Science and Engineering | Volume 29 | Number 2 | August 1967 | Pages 210-217
Technical Paper | doi.org/10.13182/NSE67-A18529
Articles are hosted by Taylor and Francis Online.
Energy spectra have been computed for protons, alpha particles, and their secondary electrons slowing down in water irradiated by 14.6-MeV neutrons. Spectra for protons and alpha particles were based on continuous slowing down theory. Anisotropy of the proton-recoil reaction and elastic nuclear collisions of charged particles were found to have negligible influence on energy spectra and the energy-loss distribution. Partitioning of the neutron first-collision dose rate among the three particles was found to be very sensitive to the cutoff energy for production of secondary electrons. An analysis based on treatment of a collisional energy loss of less than 200 eV as localized energy dissipation along a particle track showed that localized electronic energy loss is distributed among protons, alpha particles, and their secondary electrons in the respective fractions 0.530, 0.112, and 0.358.