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Division Spotlight
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.
Meeting Spotlight
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.
S. T. Perkins
Nuclear Science and Engineering | Volume 24 | Number 3 | March 1966 | Pages 284-290
Technical Paper | doi.org/10.13182/NSE66-A17640
Articles are hosted by Taylor and Francis Online.
The neutron spectrum equations are investigated for regions in which the neutron source includes both volume and surface components. The results are thereby applicable to reflected cores and reflector regions. The spectrum is analyzed in the volume-integrated P1 approximation. The difference from the corresponding bare-core relations is an additional source, plus the redefinition of the leakage parameter. It is shown, with the approximation of diffusion theory, that the leakage parameter is always nonpositive. Several simplified forms are also developed for this term. A numerical calculation is presented to show the details of the procedure, and the results are compared to a multiregion analysis.
