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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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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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
DOE extends Centrus’s HALEU production contract by one year
Centrus Energy has announced that it has secured a contract extension from the Department of Energy to continue—for one year—its ongoing high-assay low-enriched uranium (HALEU) production at the American Centrifuge Plant in Piketon, Ohio, at an annual rate of 900 kilograms of HALEU UF6. According to Centrus, the extension is valued at about $110 million through June 30, 2026.
George E. Apostolakis
Nuclear Science and Engineering | Volume 53 | Number 2 | February 1974 | Pages 141-152
Technical Paper | doi.org/10.13182/NSE74-A23340
Articles are hosted by Taylor and Francis Online.
This is a theoretical investigation of the accuracy of conventional point kinetics in a multiregion reactor without feedback. The fundamental assumption of point kinetics is the splitting of the neutron density into a product of a known constant shape function and an unknown amplitude function. The model cannot acount for the distortion of the shape of the neutron distribution due to space-dependent perturbations and this results in an error in reactivity. It is to this error that bounds are derived. This is done by using the method of weighted residuals to reduce the original eigenvalue problem to that of a real asymmetric matrix. Theorems from matrix algebra are then used to find disks in the complex plane where the eigenvalues are contained. The radii of the disks depend on the perturbation in a simple manner. Examples of space-dependent step and ramp insertion of reactivity in slab reactors demonstrate the usefulness of the bound.
