Simultaneous determination of neutron-induced fission and radiative capture cross sections from decay probabilities obtained with a surrogate reaction

Prez Snchez, R.*; Jurado, B.*; Mot, V.*; Roig, O.*; Dupuis, M.*; Bouland, O.*; Denis-Petit, D.*; Marini, P.*; Mathieu, L.*; Tsekhanovich, I.*; Ache, M.*; Audouin, L.*; Cannes, C.*; Czajkowski, S.*; Delpech, S.*; Grgen, A.*; Guttormsen, M.*; Henriques, A.*; Kessedjian, G.*; Nishio, Katsuhisa   ; Ramos, D.*; Siem, S.*; Zeiser, F.*

Reliable neutron-induced-reaction cross sections of unstable nuclei are essential for nuclear astrophysics and applications but their direct measurement is often impossible. The surrogate-reaction method is one of the most promising alternatives to access these cross sections. In this work, we successfully applied the surrogate-reaction method to infer for the first time both the neutron-induced fission and radiative capture cross sections of Pu in a consistent manner from a single measurement. This was achieved by combining simultaneously measured fission and -emission probabilities for the Pu(He, He') surrogate reaction with a calculation of the angular-momentum and parity distributions populated in this reaction. While other experiments measure the probabilities for some selected -ray transitions, we measure the -emission probability. This enlarges the applicability of the surrogate-reaction method.