Covariance matrices of Cf-252 spectrum-averaged cross sections

From the uncertainty information given in the literature the off-diagonal elements of the covariance matrices of various experimental data sets of Cf-252 averaged cross sections were generated. This information, which is often neglected, was used in a non-diagonal weighted least-square fit to evaluate a 'best' set of average cross sections. The importance of quoting the full information on uncertainties in form of a covariance matrix is demonstrated