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Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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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.
Robert P. Wichner, Roger D. Spence
Nuclear Technology | Volume 70 | Number 3 | September 1985 | Pages 376-393
Technical Paper | Nuclear Safety | doi.org/10.13182/NT85-A15964
Articles are hosted by Taylor and Francis Online.
The degree of vaporization of light water reactor core materials was estimated using a highly idealized procedure involving (a) specification of the phases that are present for both structural and fuel material, (b) estimation of the vapor pressures exerted by the individual components of each phase, and (c) assuming a degree of vaporization of each phase constituent, allowing equilibration between gaseous and condensed species within the assumed pressure vessel volume. Using this procedure, the aerosol was estimated to consist mainly of silver, indium oxide, cesium hydroxide, and cadmium for pressurized water reactors and cesium hydroxide, cesium iodide, and tellurium for boiling water reactors. If boron is included in the thermodynamic estimate, then boron will significantly alter or dominate the composition of the aerosol in the form of boron oxide and cesium borate. The structural materials make up <9% of the aerosol at 36 to 57 kg, but this figure is in good agreement with estimates from severe accident sequence analysis studies (17 kg) and from Parker (10.7 kg). The SASCHA data are used in NUREG-0772 and give much higher estimates at 295 and 250 kg.