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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
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
John C. Vigil
Nuclear Science and Engineering | Volume 29 | Number 3 | September 1967 | Pages 392-401
Technical Paper | doi.org/10.13182/NSE29-03-392
Articles are hosted by Taylor and Francis Online.
A method based on analytic continuation, which is well suited for fast digital computer application, has been applied to the point reactor kinetics equations. The most important characteristic of the method is that it yields an analytic criterion for the magnitude of the time step. This criterion is such that the time step automatically expands or contracts, depending on the behavior of the function within each interval. The use of this criterion to determine the time step guarantees that the fractional error in the results increases, at most, linearly with the number of time steps. Furthermore, the magnitude of the time step determined from this criterion can be much larger than the prompt-neutron generation time. Approximate solutions by this method were compared with some analytic solutions to the reactor kinetics equations, and the error accumulation was found, in all cases, to be within the limits predicted by the theory. Comparisons were also made with experimental transients in the Godiva and SPERT I reactors. The approximate results were found to agree well with experiment in the range of reactivity inputs where the feedback model used is valid. In a comparison with another numerical method (RTS code), analytic continuation was found to be 25 times faster.