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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
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
Standards Program
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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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. Matthes
Nuclear Science and Engineering | Volume 47 | Number 2 | February 1972 | Pages 234-237
Technical Note | doi.org/10.13182/NSE72-A22403
Articles are hosted by Taylor and Francis Online.
This paper gives a general Monte Carlo procedure for the calculation of perturbations in the reactivity of a multiplying system due to changes in system parameters (e.g., temperature, control rod positions). The procedure is based on the perturbation theory formula which gives the reactivity change δk exact up to terms of second order if the fission density distribution (and) or the corresponding adjoint function are known up to first order. As this formula makes full use of the properties of the importance (adjoint) function, a Monte Carlo procedure is developed for the evaluation of the adjoint function also.