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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
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
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.
R. Böttger, H. Klein, A. Chalupka, B. Strohmaier
Nuclear Science and Engineering | Volume 106 | Number 3 | November 1990 | Pages 377-398
Technical Paper | doi.org/10.13182/NSE90-A29065
Articles are hosted by Taylor and Francis Online.
A precision multidetector neutron time-of-flight (TOF) spectrometer and low-mass paral-lel-plate ionization chambers with a 252Cf deposit on the inner electrode are used to measure the spectral fluence of neutrons from the spontaneous fission of 252Cf in the 2- to 14-MeV energy range. Various methodological problems are carefully investigated. The influence of anisotropic efficiency in detecting the fission fragments is determined experimentally and numerically. Formulas are derived for an iterative analysis of the measured TOF spectra taking into account an inverted time scale and a nonextended dead time in the stop chain. On the basis of calculated neutron detection efficiencies, which were recently confirmed by n-p scattering experiments and proton recoil telescope measurements, it was possible to extract the spectral fluence of fission neutrons in absolute scale. The experimental data show significant deviations from a Maxwellian distribution with an energy parameter E0 = 1.42 MeV, but reasonable agreement can be achieved with cascade evaporation model calculations.
