Assessment and Propagation of the ²³⁷Np Nuclear Data Uncertainties in Integral Calculations by Monte Carlo Techniques

A new method to produce covariance or dispersion matrices for the resonance parameters of neutron cross sections was developed. The technique uses resonance shape analysis in association with Monte Carlo treatment of the uncertainties. The method was implemented in the error propagation tool MCFIT. This program provides a user-friendly textual interface for the shape analysis code REFIT. It was designed to take into account the main sources of uncertainties involved in time-of-flight measurements. Its capability is illustrated with the simultaneous analysis of ²³⁷Np capture and transmission data. The covariance matrix obtained in this work was used to interpret oscillation measurements of ²³⁷Np samples carried out in the Minerve reactor located at Cadarache.