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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
2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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August 2024
Latest News
New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
J. B. Czirr, R. L. Bramblett
Nuclear Science and Engineering | Volume 28 | Number 1 | April 1967 | Pages 62-71
Technical Paper | doi.org/10.13182/NSE67-A18668
Articles are hosted by Taylor and Francis Online.
This experiment was conducted to obtain data to be used in calculating the number of fissions produced by neutrons in bulk 239Pu as a function of neutron energy. The data provide a consistent set of group-averaged cross sections and self-shielding factors. Although self-shielding factors have been calculated from cross-section data, no previous experiments to measure the energy dependence of 239 Pu self shielding exist. A consistent set of cross sections is possible because of the wide neutron energy range over which this experiment was done. No attempt was made to determine resonance parameters, since in this experiment poor energy resolution was used to improve statistics. (Resonance parameters are, in fact, unnecessary to determine group-averaged cross sections and room-temperature self-shielding factors.) Good-geometry self-shielding factors were measured by a plutonium fission counter shielded by various thicknesses of plutonium. Average fission cross sections, total cross sections, and self-shielding factors have been determined in 11 energy groups whose end points are in the ratio of 2.15-to-1. The energy range was 2.15 eV to 10 keV. The LRL Linac neutron time-of-flight facility was used, with a neutron resolution of 0.18 μsec/m. The detector consisted of a spark chamber that was sensitive to fission fragments, facing a 0.4 mg/cm2 plutonium-239 foil. Seven Pu absorber foils ranging from 0.06 to 3 g/cm2 were used in the self-shielding measurements. This range of absorber thickness yields an adequate description of the resonance-produced surface-absorption effect throughout the above energy region.