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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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NRC cuts fees by 50 percent for advanced reactor applicants
The Nuclear Regulatory Commission has announced it has amended regulations for the licensing, inspection, special projects, and annual fees it will charge applicants and licensees for fiscal year 2025.
F. D. Judge and P. B. Daitch
Nuclear Science and Engineering | Volume 26 | Number 4 | December 1966 | Pages 472-486
Technical Paper | doi.org/10.13182/NSE66-A18418
Articles are hosted by Taylor and Francis Online.
The variational method is used to reduce the general time-dependent Boltzmann equation to a multigroup (with overlapping or nonoverlapping) form. The variation of the fundamental decay rate with material properties is then studied. The relation between energy and space transients in pulsed multiplying and pulsed moderating systems is investigated. To augment the theoretical treatment of the asymptotic decay in a pulsed multiplying system, the Nelkin buckling expansion solution for the Fourier transformed transport equation for 1/υ absorption is extended to include non-1/υ absorption and fission. The development of an improved calculational procedure (DP-L multigroup overlapping or nonoverlapping) for determining the space and time dependence of the neutron flux in pulsed multiplying systems is described. This method is then applied to the analysis of recent pulsed spectra measurements. The duration of the energy and spatial transients and the variation of the vector flux distribution from the center to the edge of an assembly are described quantitatively. It is demonstrated that spatial asymmetries in the flux could exist after the flux distribution appears asymptotic.
