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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.
P. S. Grover, L. S. Kothari, A. K. Ghatak
Nuclear Science and Engineering | Volume 31 | Number 2 | February 1968 | Pages 314-317
Technical Paper | doi.org/10.13182/NSE68-A18243
Articles are hosted by Taylor and Francis Online.
Assuming isotropic neutron scattering in beryllium, we have calculated the fundamental decay constant λ0 and the diffusion length L both in diffusion-theory approximation and according to the transport theory. A comparison of the two results enables one to comment on the range of validity of diffusion theory in crystalline moderators. We find, for example, that under the assumption of isotropic scattering, the two theories give results differing by less than 4% for B2 ≲ 0.04 cm−2 in the case of a pulsed-neutron problem and for ∑a < 0.05 cm−1 in the case of a diffusion-length problem.
