Most recent evaluated nuclear data files exhibit excellent integral performance, as shown by the very good agreement between experimental and calculated keff values over a wide range of benchmark integral experiments. | Cross-observables and cross-isotopes correlations in nuclear data from integral constraints EPJ Nuclear Sci. Technol. 4 35 2018 Nuclear Sciences E. Bauge and . Rochman published by EDP Sciences 2018 amp Technologies https epjn 2018011 Available online at https REGULAR ARTICLE Cross-observables and cross-isotopes correlations in nuclear data from integral constraints Eric Bauge1 and Dimitri A. Rochman2 1 CEA DAM DIF 91297 Arpajon France 2 Laboratory for Reactor Physics Systems Behaviour Paul Scherrer Institut Villigen Switzerland Received 31 October 2017 Received in final form 16 January 2018 Accepted 4 May 2018 Abstract. Most recent evaluated nuclear data files exhibit excellent integral performance as shown by the very good agreement between experimental and calculated keff values over a wide range of benchmark integral experiments. However the propagation of the uncertainties associated with those nuclear data to integral observables generally produces calculated distribution which are much 3 5 times wider than the experimental uncertainties. Reducing the variances of the evaluated data to achieve consistency at the integral level would lead to unreasonably narrow variances in the light of differential experimental data. One way of solving that paradox could be to allow for different observables like fission cross-sections s f the prompt fission neutron spectra x and the average multiplicity of fission neutrons n to be correlated in a Bayesian-like Total Monte- Carlo approach under constraints from integral experiments from the ICSBEP International Criticality Safety Benchmark Evaluation Project benchmark compilation. Future developments will be highlighted and restrictions imposed by the current formatting of nuclear data will be discussed. 1 Introduction and only the combinations that account well for the selected integral experiments are retained. This calibration There seems to be a contradiction between capacity of process is in
