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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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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.
Eiping Quang, Glenn F. Knoll
Nuclear Science and Engineering | Volume 110 | Number 3 | March 1992 | Pages 282-288
Technical Paper | doi.org/10.13182/NSE90-99
Articles are hosted by Taylor and Francis Online.
The cross section of the reaction 238U(n,γ)239U is measured at neutron energies of 23 and 964 keV. Photoneutron sources Sb-Be and Na-Be are calibrated using a manganese bath traceable to the National Bureau of Standards neutron source NBS-I and are provided nearly monoenergetic neutron irradiation. Neptunium-239 from the decay of 239U is chemically separated from the uranium target and is counted to determine the reaction rate. An 242Am foil is used as an absolute gamma-ray calibration standard in the determination of the induced activity. The resulting cross-section values are 491 ± 11 and 138 ± 5 mb at 23 and 967 keV, respectively.