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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
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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DOE-EM awards $74.8M Oak Ridge support services contract
The Department of Energy’s Office of Environmental Management has awarded a five-year contract worth up to $74.8 million to Independent Strategic Management Solutions for professional support services at the Oak Ridge Office of Environmental Management site in Oak Ridge, Tenn.
Tsahi Gozani
Nuclear Science and Engineering | Volume 36 | Number 2 | May 1969 | Pages 143-158
Technical Paper | doi.org/10.13182/NSE69-A19714
Articles are hosted by Taylor and Francis Online.
A detailed experimental study on the kinetics of a 238U sphere is described. The measurements involve the use of nanosecond electronics and silicon solid-state detector with two fission conversion foils: 235U and 237Np. Thus, some information on the time-energy coupling was obtained. The results show a nonexponential behavior over all time ranges. At longer times, the space and time coupling was small. At early times, the coupling between energy space and time was strong. The early time behavior of the high-energy neutrons (above 237Np threshold) appears to be exponential. The decay constant, however, is a function of position. It is shown that this exponential behavior is a result of a “pseudo-trapping” of neutrons between the fast fission threshold in 237Np and the large step in the inelastic scattering cross section of 238U.
