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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.
S. G. Carpenter, J. M. Gasidlo, J. M. Stevenson
Nuclear Science and Engineering | Volume 49 | Number 2 | October 1972 | Pages 236-239
Technical Note | doi.org/10.13182/NSE72-2
Articles are hosted by Taylor and Francis Online.
The effective delayed-neutron fractions of 235U and 239Pu have been determined for two fast critical assemblies from measurements of the absolute fission rate and the apparent reactivity worths of a calibrated 252Cf neutron source. The experimental values of βeff for the two fissile isotopes, 0.0078 to 0.00233, respectively, are in reasonable agreement with calculations. The results do not explain the 30% discrepancy in measured and calculated reactivity values in fast critical experiments.
