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Division Spotlight
Human Factors, Instrumentation & Controls
Improving task performance, system reliability, system and personnel safety, efficiency, and effectiveness are the division's main objectives. Its major areas of interest include task design, procedures, training, instrument and control layout and placement, stress control, anthropometrics, psychological input, and motivation.
Meeting Spotlight
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.
D. Shalitin, J. J. Wagschal, Y. Yeivin
Nuclear Science and Engineering | Volume 68 | Number 3 | December 1978 | Pages 243-248
Technical Paper | doi.org/10.13182/NSE78-A27303
Articles are hosted by Taylor and Francis Online.
Conditions for the reduction of the time-independent neutron transport equation to an energy-independent (one-group) equation are discussed. It is shown that a meaningful reduction is equivalent to angular flux separability into a product of an energy spectrum and a spatial and angular function. It is proven that such a separability in a finite system is possible if and only if the total cross section is energy independent, provided some auxiliary conditions are met. The physical situations in which these conditions are satisfied and the similarity to the so-called first fundamental theorem of reactor theory are discussed.