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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
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Toshihiro Yamamoto, Yoshinori Miyoshi, Takehide Kiyosumi
Nuclear Science and Engineering | Volume 145 | Number 1 | September 2003 | Pages 132-144
Technical Paper | doi.org/10.13182/NSE03-A2369
Articles are hosted by Taylor and Francis Online.
Evaluated criticality benchmark data obtained at the Static Criticality Experiment Facility (STACY) account for a large percentage of low-enriched uranium (LEU) solution systems documented in the "International Handbook of Evaluated Criticality Safety Benchmark Experiments." These data are available for validation of computer codes and nuclear data used for criticality safety analyses of LEU solution systems. The calculated keff's for the water-reflected STACY criticality experiments have been overestimated with JENDL-3.2 by ~0.7%. These overestimations were kept in mind while making modifications of the fission spectrum and the fission cross section of 235U, and the (n,p) cross section of 14N in JENDL-3.3. Because of these modifications, the keff's calculated with JENDL-3.3 were largely improved. The contributions of these modifications in JENDL-3.3 with respect to JENDL-3.2 and ENDF/B-VI.5 were investigated by performing perturbation calculations. The overestimation of the elastic-scattering cross section of 56Fe in the mega-electron-volt range was one of the reasons for the keff overestimations for the STACY experiments with JENDL-3.2. The modification of 56Fe cross sections in JENDL-3.3 reduces keff's in the STACY experiments by 0.2%. The dependence of calculated keff's on uranium concentration still exists in JENDL-3.3. The overestimation of calculated keff's for the STACY experiments with JENDL-3.3 is not insignificant and is as much as 0.6%. These problems are to be resolved in a future evaluation of the cross-section library.
