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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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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
Krystyna Kowalska
Nuclear Science and Engineering | Volume 24 | Number 3 | March 1966 | Pages 260-271
Technical Paper | doi.org/10.13182/NSE66-A17639
Articles are hosted by Taylor and Francis Online.
The problem of critical dimensions of an infinite-slab multi-layer multiplying system can be solved by a general procedure due to K. M. Case. The angular neutron distribution and the critical core size can then be found by solving the Fredholmtype integral equation with an additional critical condition. Numerical calculations have been done for the case of a multiplying slab surrounded by an infinite reflector, assuming one-energy group and isotropic scattering of neutrons, the mean number of secondary neutrons per collision in a medium-c being a variable parameter. Various approximations of the exact solution have been compared and the asymptotic theory has been found applicable in a wide range of c values in both media. 272
