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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.
Michael A. Pope, Jean Tommasi
Nuclear Science and Engineering | Volume 164 | Number 2 | February 2010 | Pages 162-184
Technical Paper | doi.org/10.13182/NSE09-22
Articles are hosted by Taylor and Francis Online.
Reactivity contributions of differences between JEFF-3.1 and ENDF/B-VI.8 were analyzed for six early MASURCA cores of the R-Z program using ERANOS 2.1. These cores were designed such that their neutron spectra would emulate that of an oxide-fueled sodium-cooled fast reactor, some containing enriched uranium and others containing depleted uranium and plutonium. Effects of modeling assumptions and solution methods both in ECCO lattice calculations and in BISTRO Sn flux solutions were first evaluated using JEFF-3.1 cross-section libraries. Comparisons were made between calculated and measured values for reactivity and several spectral indices. Reactivity effects of differences between JEFF-3.1 and ENDF/B-VI.8 were also quantified using perturbation theory analysis. The most important nuclide with respect to reactivity differences between cross-section libraries was 23Na, primarily a result of differences in the angular dependence of elastic scattering, which is more forward peaked in ENDF/B-VI.8 than in JEFF-3.1. Differences in 23Na inelastic scattering cross sections between libraries also generated significant differences in reactivity, more due to the differences in magnitude of the cross sections than to the angular dependence. The nuclide 238U was also found to be important with regard to reactivity differences between the two libraries mostly due to a large effect of inelastic scattering differences and two smaller effects of elastic scattering and fission cross sections. In the cores that contained plutonium, 239Pu fission cross-section differences contributed significantly to the reactivity differences between libraries.
