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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.
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.
W. L. Dutré, A. F. Debosscher
Nuclear Science and Engineering | Volume 62 | Number 3 | March 1977 | Pages 355-363
Technical Paper | doi.org/10.13182/NSE77-A26977
Articles are hosted by Taylor and Francis Online.
This paper presents an exact and complete statistical analysis of the neutron density fluctuations resulting from Gaussian white reactivity noise in a point reactor model with proportional power feedback, but without delayed neutrons. The analysis includes the multiplicative effect of neutron density and reactivity variations. An exact solution of the time-independent Fokker-Planck equation is found, resulting in a gamma density function for the stationary first-order probability density of the power fluctuations. The time-dependent Fokker-Planck equation is solved for the Laplace transformed function, which can be written in terms of confluent hypergeometric functions. The subsequent inversion yields the transition probability density function. The most common first- and second-order statistical characteristics, such as moments, autocovariance function, and power spectral density, are calculated and compared to the results of a linearized analysis.