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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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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Latest News
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.
P. Greebler
Nuclear Science and Engineering | Volume 3 | Number 4 | April 1958 | Pages 445-455
Technical Paper | doi.org/10.13182/NSE58-A25481
Articles are hosted by Taylor and Francis Online.
Thermal and epithermal absorption of neutrons by a cylindrical control rod are computed using two-group diffusion theory and assuming a flat source distribution for the epithermal group. Hurwitz-Roe area rule concepts are modified to take into account the nonthermal absorption by the rod and are extended to include rods that are not “black.” The effect of the control rod on the neutron economy is averaged over a cylindrical cell surrounding the rod and is expressed in terms of two-group absorption cross sections. Control rod power perturbations in a reactor are calculated from the two-group flux distributions in the cell containing the centered control rod.
