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Division Spotlight
Isotopes & Radiation
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.
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.
Guillaume Giudicelli, Kord Smith, Benoit Forget
Nuclear Science and Engineering | Volume 194 | Number 11 | November 2020 | Pages 1044-1055
Technical Paper | doi.org/10.1080/00295639.2020.1765606
Articles are hosted by Taylor and Francis Online.
A recent hybrid stochastic-deterministic calculation scheme using Monte Carlo–tallied group cross sections in a deterministic solver uses the best of both worlds for accurate and fast reactor agnostic transport simulations. However, neglecting the angular dependence of group cross sections induces large self-shielding errors in resonance groups, causing a large reactivity bias up to 300 pcm in light water reactors. To recover this error, we introduce a two-scale assembly transport calculation scheme: cross sections are tallied at the assembly level, while equivalence parameters are computed in a two-dimensional (2-D) pin cell system. We validate a novel equivalence method based on jump conditions on angular fluxes by comparing to the well-established superhomogenization method for 2-D and three-dimensional (3-D) linear source method of characteristics calculations. Test cases include 2-D and 3-D assemblies of two different enrichments with homogeneous and discretized cross-section discretizations. The linear source approximation enables using coarse source-region discretization for these hot zero-power problems. Both equivalence techniques perform similarly, recover the reactivity bias, and achieve near preservation of reaction rates, supporting this multiscale approach to equivalence.