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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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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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Latest News
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.
Scott D. Ramsey, Gregory J. Hutchens
Nuclear Science and Engineering | Volume 173 | Number 2 | February 2013 | Pages 197-205
Technical Note | doi.org/10.13182/NSE11-34
Articles are hosted by Taylor and Francis Online.
A quantity that is frequently of interest in stochastic neutronics calculations is the probability of extinction (POE), or its complement, the survival probability. Even within the simplest stochastic point kinetics formulations, the POE is typically extracted from numerical calculations or approximated. An example of the latter strategy involves the truncation of the fission multiplicity distribution at two, resulting in the “quadratic approximation.” While this methodology yields closed-form results for the POE, it is valid only for supercritical multiplication near unity. In this technical note, we attempt to obviate fission multiplicity truncation in the construction of transient and infinite time limit closed-form POE solutions. In the infinite time limit, we arrive at the necessity of solving a quintic algebraic equation; we provide a brief discussion of the mature formalism available for solving quintic equations and generate a variety of simple representations using hypergeometric series. We evaluate and discuss both the new and existing approximations in the context of an example 235U system and compare their validity over a range of supercritical multiplication factors.