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Conference Spotlight
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
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.
J. C. Hopkins, B. C. Diven
Nuclear Science and Engineering | Volume 12 | Number 2 | February 1962 | Pages 169-177
Technical Paper | doi.org/10.13182/NSE62-A26055
Articles are hosted by Taylor and Francis Online.
The ratio of neutron capture to fission cross sections, α, has been measured for U233, U235, and Pu239 at 9 incident neutron energies from 30 kev to 1000 kev. A pulsed and collimated neutron beam is passed through a target placed at the center of a large, cadmium-loaded, liquid scintillator. Capture and fission events are detected by means of their prompt gamma rays; elastic and inelastic scattering events are discarded because of their smaller pulse height. Fission is identified by the delayed pulses produced by capture in the scintillator of the fission neutrons. Corrections are applied for the fission events not followed by delayed neutron pulses and for the effect of background counts. This procedure yields values of 1 + α to an accuracy of 1 or 2%.
