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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.
S. V. G. Menon, D. C. Sahni
Nuclear Science and Engineering | Volume 76 | Number 2 | November 1980 | Pages 181-197
Technical Paper | doi.org/10.13182/NSE80-A19450
Articles are hosted by Taylor and Francis Online.
In this paper we treat the problem of resonance absorption in isolated Breit-Wigner resonances of an absorber in an infinite homogeneous mixture of the absorber and moderator with an explicit treatment of the moderator collision integral. It is shown that Fourier transform techniques can profitably be used to treat this problem. However, the treatment calls for certain ideas from the theory of distributions similar to those used by Case in singular eigenfunction theory. The formulation leads to Fredholm integral equations in the transform variable whose solution gives the integral parameter of interest, namely, the effective resonance integral directly. In the limit of zero temperature, we obtain a second-order differential equation in the transform variable and formulate an accurate and fast converging iterative scheme to extract the resonance integral from its solution. Explicit formulas are derived for the resonance integral including the effect of resonance potential interference scattering. The analysis also provides an analytical expression for the asymptotic flux distribution well below the resonance energy. Numerical results are presented to demonstrate the accuracy of the method.