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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
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
G. Lansing Blackshaw, Raymond L. Murray
Nuclear Science and Engineering | Volume 27 | Number 3 | March 1967 | Pages 520-532
Technical Paper | doi.org/10.13182/NSE86-A17617
Articles are hosted by Taylor and Francis Online.
The elastic scattering of low-energy neutrons by the nuclei of a monatomic gas, which have an isotropic Maxwellian velocity distribution, is examined in detail within the framework of classical physics. A unified mathematical treatment, which fully preserves the three-dimensional aspects of the scattering process, is employed to study the dynamics of the neutron-nuclear elastic collision. A new form of the scattering probability function in velocity space is derived under the assumption of isotropic scattering in the center-of-mass system. Unique single-integral expressions, which are valid for any analytical or numerical representations of σs(υr) and σa(υr), the microscopic scattering and absorption cross section as functions of the relative neutron-nuclear speed, are developed for the velocity scattering kernel, its spherical-harmonics weighted moments, and the total scattering and absorption probabilities. These formulations are tested by explicitly evaluating them in closed form for certain analytical cross-section representations and comparing these solutions with known results. The utility of the collision kernels for new solutions of the transport equation under conditions of variable scattering cross section is discussed.
