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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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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.
M. Segev
Nuclear Science and Engineering | Volume 91 | Number 2 | October 1985 | Pages 143-152
Technical Paper | doi.org/10.13182/NSE85-A27437
Articles are hosted by Taylor and Francis Online.
A deuterium-tritium neutron source is amplified when emitted into a body of material with appreciable (n,2n), (n,3n), and (n,f) cross sections. This amplification is described by a simple theory, approximating the strict integral transport description of the process. The distribution of neutrons in energy, from 14 MeV down to the (n,2n) threshold, is approximated by a generalized slowing down equation, which is similar in form to the infinite medium slowing down equation, and with average collision probabilities taking up the role of scattering fractions. Following a few collisions, the collision source spatial distribution resembles the fundamental mode flux distribution of a critical reactor. The average collision probability for such a source is, in diffusion theory, ∑tr/(∑tr + DB2), where B2 is the geometrical buckling of the system. This yields an expression of the form (αx+βx2)/(l + αx + βx2) for the average collision probability, where x is a representative optical thickness of the system. It has been shown by numerical means that this form for the average collision probability is generally true for centrally peaked sources in variously shaped bare bodies of any optical thickness.