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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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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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A wave of new U.S.-U.K. deals ahead of Trump’s state visit
President Trump will arrive in the United Kingdom this week for a state visit that promises to include the usual pomp and ceremony alongside the signing of a landmark new agreement on U.S.-U.K. nuclear collaboration.
Marshall F. Crouch
Nuclear Science and Engineering | Volume 2 | Number 5 | September 1957 | Pages 631-639
Technical Paper | doi.org/10.13182/NSE57-A25430
Articles are hosted by Taylor and Francis Online.
Fast neutrons are produced inside a water moderator by a Po-α-Be source used effectively as a pulsed neutron source. The slowing-down time to the Cd edge is measured with a BF3 proportional counter used with a cadmium difference technique. The mean slowing down time to O.35 ev, and the variance thereof, are found to be 5.2 µsec and 8.0 µsec2, respectively. It is shown that this is in reasonable agreement with the results of a Monte Carlo calculation, provided collisions are considered to involve whole H2O molecules when the neutron energy falls below about 1.6 ev.
