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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.
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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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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.
Jeffrey A. Favorite
Nuclear Science and Engineering | Volume 152 | Number 2 | February 2006 | Pages 180-196
Technical Paper | doi.org/10.13182/NSE06-A2574
Articles are hosted by Taylor and Francis Online.
Variational perturbation theory is applied to internal interface perturbations in neutral-particle inhomogeneous transport problems. The leakage from a radioactive system is the quantity of interest. The Schwinger and Roussopolos variational functionals are used with volume- and surface-integral formulations of the integrals of perturbed quantities. In numerical one-dimensional spherical tests of source radius perturbations, the Roussopolos functional in the surface-integral formulation worked better when the source was large, and the Schwinger functional in the volume-integral formulation worked better when the source was small. A new variational functional is presented that formally allows a combination of the Schwinger and Roussopolos functionals; the contribution of each to the total estimate is adjusted with a parameter introduced in one of the trial functions. When the parameter is correctly chosen, the new functional is generally more accurate than either the Schwinger or Roussopolos functional alone. An analytic monodirectional slab transport problem is also considered.