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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.
H. G. Kaper
Nuclear Science and Engineering | Volume 28 | Number 3 | June 1967 | Pages 415-425
Technical Paper | doi.org/10.13182/NSE67-A28956
Articles are hosted by Taylor and Francis Online.
An approximate theory for the slowing down of neutrons in a nonmultiplying medium with plane symmetry is described. The theory is based on an approximate form of the transfer function for elastic scattering under the hypothesis that the mass number of the moderator is larger than one. In the A−N approximation the slowing down equation is reduced to a finite system of differential equations with respect to the lethargy variable. A detailed study has been made of the results obtained in the A−N approximation with N = 0 and N = 1. Special attention has been paid to a comparison of the A−1 approximation with age theory and asymptotic theory.
