Uncertainty analysis of Lead cross sections on reactor safety for ELECTRA
1 Division of Applied Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden
2 Nuclear Research and Consultancy Group (NRG), Petten, The Netherlands
The Total Monte Carlo (TMC) method was used in this study to assess the impact of Pb-206, 207 and 208 nuclear data uncertainties on keff , βeff, coolant temperature coefficient, the coolant void worth for the ELECTRA reactor. Relatively large uncertainties were observed in the keff and the coolant void worth for all the isotopes with significant contribution coming from Pb-208 nuclear data. The large Pb-208 nuclear data uncertainty observed was further investigated by studying the impact of partial channels on the keff and the βeff. Various sections of ENDF file: elastic scattering (n, el), inelastic scattering (n, inl), neutron capture (n, γ), (n, 2n), resonance parameters and the angular distribution were varied randomly and distributions in keff and the βeff obtained. The dominant contributions to the uncertainty in the keff from Pb-208 came from uncertainties in the resonance parameters; however, elastic scattering cross section and the angular distribution also had significant impact. The impact of nuclear data uncertainties on the βeff was observed to be small.
Key words: TMC / nuclear data uncertainty / lead isotopes / safety parameters / ELECTRA / fuel cycle
© Owned by the authors, published by EDP Sciences, 2014