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Division Spotlight
Nuclear Nonproliferation Policy
The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
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. R. Fields, G. L. Pyle, M. G. Inghram, H. Diamond, M. H. Studier, W. M. Manning
Nuclear Science and Engineering | Volume 1 | Number 1 | March 1956 | Pages 62-67
Technical Paper | doi.org/10.13182/NSE56-A17658
Articles are hosted by Taylor and Francis Online.
The effective pile neutron capture cross sections of the heavier Pu isotopes have been measured by irradiations, in the Chalk River Reactor (NRX) and in the Materials Testing Reactor. The values in barns for Pu240, Pu241, Pu242, Pu243, Pu244, and Pu245 were found to be: 530 ± 50, 390 ± 80, 30 ± 10, 170 ± 90, 1.5 ± 0.3, and 260 ± 145, respectively. In addition, a thermal neutron absorption cross section of 1450 ± 250 barns was found for Pu241 and a thermal neutron fission cross section of 1060 ± 210 barns for Pu241. Using these cross sections and an assumed flux of 3 × 1014 cm-2 sec-1, curves were calculated and plotted showing the variation in composition of plutonium as a function of integrated flux.
