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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.
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.
P. K. Job, M. Srinivasan, V. R. Nargundkar
Nuclear Technology | Volume 51 | Number 1 | November 1980 | Pages 87-96
Technical Note | Reactor | doi.org/10.13182/NT80-A32560
Articles are hosted by Taylor and Francis Online.
A series of subcritical multiplication experiments was conducted at Purnima Laboratories, Trombay, on a thick BeO-reflected 233U (98.2 wt% enrichment) uranyl nitrate solution system. The core tank was a rectangular parallelepiped of 0.11− × 0.11−m2 sectional area attached to the bottom of a glove box. Multiplication measurements were carried out with uranyl nitrate solutions in the uranium concentration range of 25 to 150 kg/m3 corresponding to H/233U ratios in the range of 1200 to 200. The maximum quantity of 233U-enriched uranium used was 0.12 kg and the corresponding multiplication was ∼5. Boric acid solutions, equivalent in terms of thermal-neutron absorption to the uranium solutions, were used to eliminate the unmultiplied neutron background and to calibrate the neutron detection system. Extrapolated critical heights determined from plots of inverse multiplication were used to obtain the keff of the subcritical assembly with the help of the Trombay Criticality Formula. Absolute multiplication and keff were also deduced independently from the observed multiplication data relative to a reference dummy core. The experimental keff results are found to be in good agreement with detailed transport theory and Monte Carlo calculations.
