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Conference 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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Powering the future: How the DOE is fueling nuclear fuel cycle research and development
As global interest in nuclear energy surges, the United States must remain at the forefront of research and development to ensure national energy security, advance nuclear technologies, and promote international cooperation on safety and nonproliferation. A crucial step in achieving this is analyzing how funding and resources are allocated to better understand how to direct future research and development. The Department of Energy has spearheaded this effort by funding hundreds of research projects across the country through the Nuclear Energy University Program (NEUP). This initiative has empowered dozens of universities to collaborate toward a nuclear-friendly future.
Edgar Kiefhaber
Nuclear Science and Engineering | Volume 111 | Number 2 | June 1992 | Pages 197-204
Technical Note | doi.org/10.13182/NSE92-A23933
Articles are hosted by Taylor and Francis Online.
For high-accuracy criticality calculations, one should take into account the difference in the energy distributions between prompt and delayed fission neutrons. In steady-state reactor calculations, it is usually assumed that delayed and prompt neutrons are emitted with the same energy distribution. This approximation may lead to systematic deviations in keffof between −0.2 and +0.05%. While for typical cores of liquid-metal-cooled fast reactors and corresponding critical assemblies the effect is usually fairly small, it may become more important for low-enriched k∞ experiments and for highly enriched, high-leakage cores. For group cross-section adjustment procedures usually covering a wide range of critical assemblies with fairly different nuclear characteristics, a proper treatment of the energy distributions of delayed neutrons could be particularly important for excluding systematic differences as far as possible.