Reevaluation and Validation of the ²⁴¹Pu Resonance Parameters in the Energy Range Thermal to 20 eV

A new SAMMY analysis of the ²⁴¹Pu resonance parameters from thermal to 20 eV is presented. This evaluation takes into account the trends given by integral experiments [post-irradiation experiments performed in French pressurized water reactors (PWRs)]. Compared to the previous evaluations performed by Derrien and de Saussure, the capture cross section increases especially in the 0.26-eV resonance. It is shown that the new resonance parameters proposed in this work improve the prediction of the ²⁴²Pu buildup in a PWR, which was significantly underestimated with the previous evaluations.