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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
DTE Energy studying uprate at Fermi-2, considers Fermi-3’s prospects
DTE Energy, the owner of Fermi nuclear power plant in Michigan, is considering an extended uprate for Unit 2 that would increase its 1,100-MW generation capacity by 150 MW.
Bal Raj Sehgal, Rubin Goldstein
Nuclear Science and Engineering | Volume 25 | Number 2 | June 1966 | Pages 174-182
Technical Paper | doi.org/10.13182/NSE66-2
Articles are hosted by Taylor and Francis Online.
Resonance absorption in heterogeneous media with intermediate-mass moderators is investigated under the assumption that the flux is spatially flat in each region. Intermediate resonance parameters are introduced for scattering by all species present in the system and an intermediate resonance approximation is developed for calculating them. An improved rational representation for the lump escape probability is used and the calculation of the Dancoff factor is modified to account for the intermediate nature of the scattering-removal process by the outside moderator. The resonance integrals from the intermediate resonance approximation are compared with those from Monte Carlo and ZUT computer code calculations for the 6.7-eV resonance of 238U. The intermediate-resonance approximation results are found to be in good agreement with the Monte Carlo results. The ZUT results have large errors for heavy moderators, especially in undermoderated systems. Equivalence among heterogeneous systems and between heterogeneous and homogeneous systems is discussed. In the former case, an equivalence through the intermediate parameters is established.
