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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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Nuclear Technology
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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.
R. A. Lillie, R. G. Alsmiller, Jr., J. T. Mihalczo
Nuclear Technology | Volume 43 | Number 3 | May 1979 | Pages 373-381
Technical Paper | Accelerator | doi.org/10.13182/NT79-A19225
Articles are hosted by Taylor and Francis Online.
A number of Type 316 stainless-steel right circular cylindrical shells of varying lengths have been analyzed using two-dimensional discrete-ordinates transport methods together with first- and last-flight particle estimators to aid in the design of neutron collimators for the Tokamak Fusion Test Reactor (TFTR). In the TFTR, the 14-MeV neutron source has a very large spatial extent, and the collimators must be designed to allow spectral measurements that refer to only a small spatial region of this extended source. The analysis identifies the 14-MeV neutrons from scattering in the Type 316 stainless steel immediately adjacent to the collimator opening as the dominant contributor to detector background. Collimator lengths >0.60 m were found sufficient to attenuate uncollided background neutrons for reasonable source-detector distances. The lower energy (<13.8 MeV) neutron background and gamma background were not found to be significant.
