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Division Spotlight
Decommissioning & Environmental Sciences
The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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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ANS designates Armour Research Foundation Reactor as Nuclear Historic Landmark
The American Nuclear Society presented the Illinois Institute of Technology with a plaque last week to officially designate the Armour Research Foundation Reactor a Nuclear Historic Landmark, following the Society’s decision to confer the status onto the reactor in September 2024.
G. P. Calame, F. D. Federighi, P. A. Ombrellaro
Nuclear Science and Engineering | Volume 10 | Number 1 | May 1961 | Pages 31-39
Technical Paper | doi.org/10.13182/NSE61-A25926
Articles are hosted by Taylor and Francis Online.
A variational procedure for calculating thermal cross sections and diffusion theory parameters is described. The method permits the calculation of an approximate lethargy-dependent Wigner Wilkins flux spectrum for a region as a linear combination of two lethargy- and temperature-dependent base spectra. The coefficients for linearly combining the base spectra are provided by the theory and once the coefficients are calculated the flux is determined. The average microscopic cross sections and diffusion theory parameters for the region are calculated from a flux weighted average of lethargy-dependent microscopic cross sections and diffusion constants. Cross sections and diffusion theory parameters calculated in this manner agree well with those obtained from the SOFOCATE code.
