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Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.
Genn Saji
Nuclear Science and Engineering | Volume 32 | Number 1 | April 1968 | Pages 93-100
Technical Paper | doi.org/10.13182/NSE68-A18828
Articles are hosted by Taylor and Francis Online.
An explicit time-dependent two-group flux, expressed by a series of space modes, is established when a forced oscillation is applied to a reactor. The self-consistent time-dependency method developed here minimizes necessary mathematical transformations and enables one to clearly visualize the physical reasons why the higher space modes are only excited at high frequencies. The conditions necessary for a particular higher space mode to be appreciably excited and detected are discussed in detail. The results show that the major factor is due to the increase of the input frequency as compared with the decay constants of several higher space modes at high frequencies. This method was applied to the NORA reactor for which the space-dependent transfer functions have been measured. Results of the calculations closely agree with the published experimental results as well as with theoretical gain and phase shift curves obtained by the conventional modal expansion-Laplace transform method. The relative amplitude of each higher space mode with respect to the fundamental mode shows the rate of convergence of the modal expansion method.