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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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.
F. T. Avignone III, L. P. Hopkins, Z. D. Greenwood
Nuclear Science and Engineering | Volume 72 | Number 2 | November 1979 | Pages 216-221
Technical Paper | doi.org/10.13182/NSE79-A19465
Articles are hosted by Taylor and Francis Online.
The theoretical beta spectrum of the thermal fission fragments of 235U in secular equilibrium was calculated using recent fission yields, nuclear decay scheme data, and very recent semi-empirical mass formulas to predict beta Q values of nuclides with unknown energy level structure. Better agreement with experiment is achieved when these isotopes are assumed to contain all of the excited states of isotopes with known decay schemes with the same atomic number Z and with neutron numbers N differing by even integers. The beta branching ratios for the unknown isotopes were assumed to be the renormalized collection of branching ratios found in all known isotopes of the families described above. The results obtained with these narrower restrictions are in better general agreement with experiment than those that replace the excited states and branching ratios of the unknown nuclides with those obtained by taking broad averages over known isotopes. There still appears to be some disagreement between theory and experiment, particularly at the high-energy end of the spectrum.