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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.
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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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
DOE extends Centrus’s HALEU production contract by one year
Centrus Energy has announced that it has secured a contract extension from the Department of Energy to continue—for one year—its ongoing high-assay low-enriched uranium (HALEU) production at the American Centrifuge Plant in Piketon, Ohio, at an annual rate of 900 kilograms of HALEU UF6. According to Centrus, the extension is valued at about $110 million through June 30, 2026.
C. W. J. McCallien
Nuclear Science and Engineering | Volume 50 | Number 3 | March 1973 | Pages 290-293
Technical Note | doi.org/10.13182/NSE73-A28982
Articles are hosted by Taylor and Francis Online.
Exact and first-order perturbation formulas that give changes in the eigenvalue of the discrete multigroup neutron diffusion equation are obtained. Various errors arising during the evaluation of these formulas are discussed. It is shown that for exact theory to give greater precision than first-order theory the fluxes must be sufficiently well converged to display the changes in them due to the perturbation. The reader is encouraged to assess the likely outcome of errors in his own calculations.
