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Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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2024 ANS Winter Conference and Expo
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Orlando, FL|Renaissance Orlando at SeaWorld
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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
W. G. Davey
Nuclear Science and Engineering | Volume 44 | Number 3 | June 1971 | Pages 345-371
Technical Paper | doi.org/10.13182/NSE71-A20166
Articles are hosted by Taylor and Francis Online.
Experimental values (apart from thermal-neutron data) of the number of prompt neutrons per fission () for 232Th, 233U, 234U, 235U, 238U, 239Pu, 240Pu, and 241Pu over the energy range from 0 to 15 MeV up to February 1970 are evaluated to derive the best available data, primarily for fast reactor analysis. Limited comments are made on data published subsequently. Data are renormalized where necessary to the latest recommended value (3.756) for for 252Cf. Many of the existing lower energy data for 233U and 235U indicate a nonlinear energy dependence that would be of significance for fast reactor analysis, but a limited number of recent specific studies on 235U strongly support linear dependence, and the existence of low-energy structure is not established. The more limited low-energy measurements on 239Pu indicate little, if any, structure. At energies above several MeV the normally assumed linear energy dependence of is more applicable, but the occurrence of the (n, n′f) and (n, 2nf) reactions in addition to the (n, f) reaction introduces a nonlinear dependence that is generally small but may be of significance for some isotopes. Consideration of the effects of first-. second-, and third-chance fission [(n, f), (n, n′f), and (n, 2nf) reactions] gives a good fit to the single case, 235U, in which a test can be made and these effects are considered in the evaluation of other isotopes.