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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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ANS and the U.K.’s NI announce reciprocal membership agreement
With President Trump on a state visit to the U.K., in part to sign a landmark new agreement on U.S.-U.K. nuclear collaboration, a flurry of transatlantic partnerships and deals bridging the countries’ nuclear sectors have been announced.
The American Nuclear Society is taking an active role in this bridge-building by forming a reciprocal membership agreement with the U.K.’s Nuclear Institute.
J. W. Boldeman, J. Fréhaut, R. L. Walsh
Nuclear Science and Engineering | Volume 63 | Number 4 | August 1977 | Pages 430-436
Technical Paper | doi.org/10.13182/NSE77-A27060
Articles are hosted by Taylor and Francis Online.
Corrections of the large liquid scintillator measurements by Boldeman et al. and Soleilhac et al. for the delayed gamma rays from fission have produced consistent values for the average number of prompt neutrons () produced in the fission of 235U. The absolute value of for thermal-neutron fission is 2.389 ± 0.009, and the energy dependence is approximately linear. The data do not support the existence of fine structure between 200 and 600 keV nor the broad step-like structural dependence found in recent evaluations. However, there is the suggestion of a slight flattening of the curve representing the data between 250 and 600 keV.
