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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.
Feroz Ahmed, A. K. Ghatak
Nuclear Science and Engineering | Volume 33 | Number 1 | July 1968 | Pages 106-118
Technical Paper | doi.org/10.13182/NSE68-A20922
Articles are hosted by Taylor and Francis Online.
We report the results of some calculations of the fundamental mode decay constant (and the corresponding eigenfunction) of the neutron transport operator in slabs and spheres of various sizes. The assemblies are assumed to be homogeneous and nonmultiplying with absorption cross section varying as 1/v. The scattering is assumed to be isotropic in the laboratory system, and parameters are chosen to represent the scattering by beryllium. The integral equations were solved by the multigroup technique, and calculations show that the fundamental mode eigenvalue for a slab is bounded by (v ∑)min whereas no bound exists for a spherical assembly. The solutions wherever possible are compared with the corresponding exp(iBx) theory results, and the implications for experiments are discussed. The nonseparability of the energy and space dependence of the asymptotic flux has been shown explicitly, and its consequences on the extrapolation distance have been pointed out.