Evaluation of the thermal neutron capture cross section of Am

Mizuyama, Kazuhito; Iwamoto, Nobuyuki  ; Iwamoto, Osamu  

The accuracy of nuclear data for the minor actinides (MAs) included in the high level radioactive wastes which have the long term radiotoxicity is required to be improved for the environmental load reduction technique. However, there is large discrepancy among the previous measurements for MAs. The Cadmium(Cd)-ratio method is the analysis method to deduce the and the s-factor by using the Cd-ratio given by the reaction rates without(with) the Cd-filter. The s-factor is defined by the normalized resonance integral by after subtracting 1/v component. Since there are lower resonances than the cut-off energy in Am, it is necessary to correct the effect of them in order to deduce the accurately. In this study, we evaluated the effect of the lower resonances than the cut-off energy as the correction of s-factor from the JENDL-4.0, and corrected the existing the data. As a result, the consistency among the measurements was improved.