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We investigated the 238U(d,p) reaction as a surrogate for the n+238U reaction. For this purpose we measured for the first time the γ-decay and fission probabilities of 239U* simultaneously and compared them to the corresponding neutron-induced data. We present the details of the procedure to infer the decay probabilities, as well as a thorough uncertainty analysis, including parameter correlations. Calculations based on the continuum-discretized coupled-channels method and the distorted-wave Born approximation (DWBA) were used to correct our data from detected protons originating from elastic and inelastic deuteron breakup. In the region where fission and γ emission compete, the corrected fission probability is in agreement with neutron-induced data, whereas the γ-decay probability is much higher than the neutron-induced data. We have performed calculations of the decay probabilities with the statistical model and of the average angular momentum populated in the 238U(d,p) reaction with the DWBA to interpret these results. [ABSTRACT FROM AUTHOR]

We have measured the fission probabilities of 242Am, 243Cm, and 244Cm induced by the transfer reactions 243Am(³He,4He), 243Am(³He,r), and 243Am(³He,d), respectively. The details of the experimental procedure and a rigorous uncertainty analysis, including a correlation matrix, are presented. For 243Cm our data show clear structures well below the fission threshold. To our knowledge, it is the first time that these structures have been observed for this nucleus. We have compared the measured fission probabilities to calculations based on the statistical model to obtain information on the fission barriers of the produced fissioning nuclei. [ABSTRACT FROM AUTHOR]

Relative values of the neutron-induced fission cross section σ(n,f) of 242Pu have been measured with respect to the standard ¹H(n,p) elastic scattering cross section, at average energies of 1.0, 1.4, and 1.9MeV. The measurements are part of an international effort to reduce uncertainties and provide independent nuclear data relevant for fast-spectrum reactors. The shape of the measured cross section is in good agreement with data from Tovesson et al. [Phys. Rev. C 79, 014613 (2009)] and with the most recent data from Matei et al. [Phys. Rev. C 95, 024606 (2017)], but disagrees with the shapes of ENDF/B-VII.1 and JEFF3.2 evaluations. Absolute values of σ(n,f), obtained under some assumptions, indicate an overestimation of σ(n,f) in the evaluated libraries at 1.0 and 1.4MeV, while a good agreement is found with ENDF/B-VII.1 at 1.9MeV. A careful analysis of the impact of scattered neutrons and anisotropy of the fission fragment angular distribution has been performed. The measurement of the neutron flux by means of a proton-recoil detector is discussed. A comprehensive study of corrections applied to the data, of associated uncertainties, and of correlations between the measurements at the different energies is presented. [ABSTRACT FROM AUTHOR]