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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.
Lung-Kwang Pan
Nuclear Technology | Volume 89 | Number 1 | January 1990 | Pages 116-125
Technical Paper | Technique | doi.org/10.13182/NT90-A34363
Articles are hosted by Taylor and Francis Online.
Destructive gamma-ray analysis of spent-fuel rods from the Taiwan Research Reactor has been performed at the Institute of Nuclear Energy Research. The purpose of the analysis is twofold: to identify the radioactivities, burnup values, and other essential parameters of spent-fuel rods, and to bridge the gap between the predicted and the actual values. The samples of fuel rods are taken from two kinds of irradiated materials: natural uranium metal and uranium dioxide pellets. Each sample is dissolved in nitric acid and diluted to 100 cm3; the uranium in each of these samples is identified down to the order of 10−10 g/cm3 by mass spectroscopy. A high-resolution, high-purity germanium detector coupled with a multichannel analyzer is used to detect 38 multiscaling gamma spectra within a 160-day period. Radioactivities of the evaluated fission products are compared with data from other works and with calculations using the ORIGEN-II code. Eleven of the 18 fission product values are found to be within 20% agreement with the calculated values. Deviations might be due to either an incorrect library file of cumulative fission product yields being used for the theoretical estimates, or to an overestimation of the thermal neutron flux during fuel rod irradiation. Results also indicate that although measurement of the 137Cs activity is an excellent indicator for burnup distribution, the cesium migration might lead to a misinterpretation of the data. Furthermore, the ratio of the activity of either 134Cs or 154Eu to 137Cs can eliminate the migratory effect and give a better approximation of burnup distribution along the axial direction of a spent-fuel rod.
