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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.
R. G. Fluharty, F. B. Simpson, and G. J. Russell, J. H. Menzel
Nuclear Science and Engineering | Volume 35 | Number 1 | January 1969 | Pages 45-69
Technical Paper | doi.org/10.13182/NSE69-A21113
Articles are hosted by Taylor and Francis Online.
Pulsed reactors are being investigated for the purpose of producing high-intensity pulsed-neutron beams for research. Leakage-emission-time-distribution measurements as a function of neutron energy have been carried out using the Resselaer Polytechnic Institute (RPI) electron linear accelerator in conjunction with a disk chopper and neutron diffraction spectrometer. Data were obtained simultaneously with the chopper and crystal spectrometer by looking at opposite sides of the moderator. This experiment was designed to investigate the importance of different variables in determining the pulse characteristics of moderators. The eventual objective is to optimize the maximum thermal-neutron intensity and minimum pulse width from pulsed-fission-neutron sources. Neutron time and energy distributions were measured for light water, polyethylene, Lucite (a metacrylate plastic), powdered zirconium hydride, and ammonia. The water, polyethylene, and zirconium-hydride samples were measured at room temperature and all the materials except water were also measured at liquid-nitrogen temperature. The effects on pulse characteristics of homogeneously poisoning light water samples were studied, as well as the effects of heterogeneously poisoning polyethylene. The effect of varying the thickness of the moderator was also investigated. Pulse widths at half-maximum of 11 µsec at 0.05096 eV and 24 µ sec at 0.01274 eV were observed for solid ammonia and heterogeneously poisoned polyethylene samples. For neutron energies between 0.08 and 0.01274 eV, solid ammonia gave the best observed figure of merit, peak intensity/ (FWHM)2. The data show that neutron pulse characteristics from a moderator can be altered significantly by varying the material and its temperature, as well as by adding poison and optimizing the geometry. Time distributions were observed in the energy region of 0.012 to 0.63 eV. The time resolution, in this energy region, for the diffraction spectrometer ranged from 2.8 to 10.8 µ sec compared with 7.6 µ sec for the chopper.
