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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
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Albuquerque, NM|The University of New Mexico
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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.
E. F. Seleznev, V. Bereznev, I. Chernova
Nuclear Science and Engineering | Volume 193 | Number 5 | May 2019 | Pages 495-505
Technical Paper | doi.org/10.1080/00295639.2018.1542866
Articles are hosted by Taylor and Francis Online.
This paper proposes partial neutron transport equations for stationary and transient calculations. The partial equations of neutron transport are based on separately following neutrons born from external source, prompt fission neutrons, and delayed neutrons. The delayed neutrons are described by a system of equations containing one equation for each group. The paper defines the parameters of these equations and presents the results of fast neutron reactor benchmark calculations.
Determination of the field of the external source neutrons in the system of partial equations provides a natural transfer of the source power (in units of neutrons per second) to the core power of energy release from the interaction of the external source neutrons in the reactor core (in units of watt). Thus, an external source neutron is used for the initial normalization of the neutron field based on the required reactor power. Operating with the field of delayed neutrons, in contrast to the field of concentrations of delayed neutron precursors, provides a quantitative assessment of the interaction of these neutrons with the reactor environment, and thus, assesses their contribution to the reactivity effects in fast reactors.
Partial neutron transport equations allow us to extract additional information about the time behavior of the fast neutron reactor.