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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
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
M. Carta, A. D'Angelo
Nuclear Science and Engineering | Volume 133 | Number 3 | November 1999 | Pages 282-292
Technical Paper | doi.org/10.13182/NSE99-A2088
Articles are hosted by Taylor and Francis Online.
Accelerator-driven systems (ADS) for nuclear waste transmutation will periodically need absolutely calibrated measurements of the subcriticality level. These measurements will allow both the check of the subcriticality margin during the ADS operation life and the related comparison between the experimental and foreseen fuel cycle reactivity effect. Until now, the possibility of absolute (source-jerk-type) reactivity measurements, to be made just after external source breakoff, has been mentioned in ADS proposals.Complementary reactivity measurement techniques are investigated to analyze the ADS response to harmonic modulation of the external neutron source. The point-kinetics approximation is used to test the method by numerical simulations. To take into account spatial effects, a multimode case is finally investigated. Results show that in the case of ADS subcritical systems, the theory of an absolute "reactimeter" may be formulated. The need for explicit transport calculations, before any possible experimental validation, is also mentioned.
