Uncertainty Quantification in the Summation Method for Nuclear Reactor Antineutrinos

The summation method was first used by P. Vogel and collaborators in 1981 to calculate the antineutrino spectra generated by ^235,238U and ^239,241Pu to predict the antineutrino spectrum generated by a nuclear reactor. That pioneering work used the fission yield and decay data from ENDF/B-V. We have lately used the ENDF/B-VIII.0 and JEFF-3.1.1 libraries with the same purpose, of particular interest now given the significant current number of nuclear reactor antineutrino experiments worldwide. Uncertainty quantification is a noteworthy aspect of the calculation, which we have addressed by developing cumulative fission yield covariance matrices using the independent fission yield correlations from the GEF code, coupled with the evaluated libraries yield uncertainties and the ENDF/B-VIII.0 decay branching ratios. Additionally, beta-minus decay intensity correlations were also included. A comparison of the summation IBD antineutrino yields with those obtained from the conversion method as well as from the Daya Bay fuel evolution measurements will be presented.