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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.
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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
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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.
H. van Dam
Nuclear Science and Engineering | Volume 129 | Number 3 | July 1998 | Pages 273-282
Technical Paper | doi.org/10.13182/NSE98-A1981
Articles are hosted by Taylor and Francis Online.
An analysis is presented of reactor dynamics during inherent shutdown and recriticality after loss of cooling without scram. The influence of the strength of external neutron sources is studied, and the dynamics of fission product decay heat is explicitly taken into account. It is shown that decay heat and (in thermal reactors) xenon dynamics play a dominant role in inherent reactor shutdown. Fission power level at first spontaneous recriticality is determined by both the strength of the external/inherent neutron sources and the reactivity ramp rate induced by xenon decay and cooling down of the subcritical reactor core. The first power surge after recriticality is only very weakly dependent on the external/inherent neutron source strength, and the amplitude of fission power oscillations is mainly determined by the reactivity ramp rate at first recriticality. Frequency and stability of the power oscillations after recriticality depend on the thermal inertia of the core and the power-reactivity defect. Stability is slightly deteriorated by the fission product decay dynamics, but the influence of xenon dynamics is negligible.
