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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.
Richard M. Roberds, Charles J. Bridgman
Nuclear Science and Engineering | Volume 64 | Number 2 | October 1977 | Pages 332-343
Technical Paper | doi.org/10.13182/NSE77-A27374
Articles are hosted by Taylor and Francis Online.
A space-angle synthesis (SAS) method is developed for the steady-state, two-dimensional transport of neutrons and secondary gamma rays from a point source of simulated nuclear-weapon radiation in air. The method is validated by applying it to the problem of neutron transport from a point source in air over a ground interface, and then comparing the results to those obtained by DOT, a discrete-ordinates code. In the method, the energy dependence of the Boltzmann transport equation is treated in the standard multigroup manner. The angular dependence is treated by expanding the flux in specially tailored trial functions and applying the method of weighted residuals that analytically integrates the transport equation over all angles. The trial functions used in the expansion are composed of combinations of selected trial solutions, the trial solutions being shaped ellipsoids that approximate the angular distribution of the neutron flux in one-dimensional space. Differences between DOT and SAS tissue-dose calculations at distances >60 m from the source were generally under 10% and decreased with increasing source or receiver height. Computer computational time was decreased by a factor of ∼7.