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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
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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.
Y. Gur, S. Yiftah
Nuclear Science and Engineering | Volume 65 | Number 3 | March 1978 | Pages 468-476
Technical Paper | doi.org/10.13182/NSE78-A27178
Articles are hosted by Taylor and Francis Online.
The currently used formalism for neutron cross-section representation in the unresolved resonance energy range is based on the statistical parameters of the population of Breit-Wigner resonances. The present work introduces practical formalisms, based on parametric representation of the shielding factor curves, by which the values of effective cross sections can be obtained simply and quickly in the unresolved range, and suggests their use for neutron data representation. These formalisms were found to be compatible with such existing codes as MC2, ETOX, HAMMER, ENDRUN, and MIGROS, and with such existing nuclear data files as ENDF/B and KEDAK. Each formalism is based on one interpolation scheme in temperature and one in σ0. The accuracy of four schemes in temperature and three schemes in σ0 was checked. Of these, three temperature schemes and one σ0 scheme were found to have better than 1% accuracy in the entire unresolved region, thus yielding a formalism with better than 2% accuracy for representation. Observed spatially dependent self-shielding factors are transformed into pseudo-background cross-section-dependent (Bondarenko-type) self-shielding factors. Numerical values of the transformation for 235U and 239Pu self-shielding factors are given. It is shown that the formalisms can be used for the preprocessing of current nuclear data files in the unresolved range.