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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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.
John T. Mihalczo
Nuclear Science and Engineering | Volume 47 | Number 3 | March 1972 | Pages 290-301
Technical Paper | doi.org/10.13182/NSE72-A22415
Articles are hosted by Taylor and Francis Online.
A series of dynamic measurements has been performed with a multiplying assembly in which a rotating beryllium reflector (worth 4.8 dollars in reactivity) moved past an unreflected core surface ∼60 times/sec at a speed of 264 m/sec. A pulse of 14.1-MeV neutrons was injected into the assembly each time the rotating reflector attained a position for which the reactivity of the assembly was maximum. The time distribution of neutrons after the injection of the pulse was measured in the core and adjacent to a 10.16- × 10.16- × 3.81-cm polyethylene scatterer which provided a pulse of thermal leakage neutrons. The maximum prompt-neutron multiplication of the assembly, which was reflected with iron on all sides but one and contained 58.6 kg of highly enriched uranium metal at delayed criticality, was varied from 75 to 285 by fuel loading changes. This assembly with a maximum prompt-neutron multiplication of 285 produced fast-neutron pulses with a width at half-maximum of 3.9 μsec, with a peak-to-minimum ratio of 12,400 and with 80% of the power in the pulse. These pulses, when thermalized by the scatterer, were broadened to a width at half-maximum of 20.9 μsec with a peak-to-minimum power ratio of 1590. The number of thermal neutrons leaking from the outer surface of the scatterer was 3.3 × 10−5 n/(cm2 fission).