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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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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.
I. Pázsit, A. Jonsson
Nuclear Science and Engineering | Volume 167 | Number 1 | January 2011 | Pages 61-76
Technical Paper | doi.org/10.13182/NSE10-15
Articles are hosted by Taylor and Francis Online.
The dynamic space- and frequency-dependent response of a molten salt reactor (MSR) to stationary perturbations is investigated in a simple analytical model. The Green's function of the system is investigated in the general case of arbitrary fuel recirculation velocity and in the limiting case of infinite fuel velocity, which permits closed-form solutions in both the static and dynamic cases. It is found that the amplitude of the induced noise is generally higher and the domain of the point kinetic behavior valid up to higher frequencies than in a corresponding traditional system. This is due to the differing behavior of the delayed neutron precursors as compared to the traditional case. The MSR equations are not self-adjoint and the adjoint equation and adjoint function have to be constructed, which is also done here. Finally, the space-dependent neutron noise, induced by propagating perturbations of the absorption cross section, is calculated. A number of interesting properties that are relevant to full-size MSRs are found and interpreted. The results are consistent with those in traditional systems, but the domains of various behavior regimes (point kinetic, space dependent, etc.) are shifted to higher frequencies or system sizes.