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Background: Multinucleon transfer reactions (MNT) are a competitive tool to populate exotic neutron-rich nuclei in a wide region of nuclei, where other production methods have severe limitations or cannot be used at all. Purpose: Experimental information on the yields of MNT reactions in comparison with theoretical calculations are necessary to make predictions for the production of neutron-rich heavy nuclei. It is crucial to determine the fraction of MNT reaction products which are surviving neutron emission or fission at the high excitation energy after the nucleon exchange. Method: Multinucleon transfer reactions in 136 Xe + 238 U have been measured in a high-resolution γ -ray/particle coincidence experiment. The large solid-angle magnetic spectrometer PRISMA coupled to the high-resolution Advanced Gamma Tracking Array (AGATA) has been employed. Beamlike reaction products after multinucleon transfer in the Xe region were identified and selected with the PRISMA spectrometer. Coincident particles were tagged by multichannel plate detectors placed at the grazing angle of the targetlike recoils inside the scattering chamber. Results: Mass yields have been extracted and compared with calculations based on the GRAZING model for MNT reactions. Kinematic coincidences between the binary reaction products, i.e., beamlike and targetlike nuclei, were exploited to obtain population yields for nuclei in the actinide region and compared to x-ray yields measured by AGATA. Conclusions: No sizable yield of actinide nuclei beyond Z = 93 is found to perform nuclear structure investigations. In-beam γ -ray spectroscopy is feasible for few-neutron transfer channels in U and the −2p channel populating Th isotopes.

The fusion excitation function of 32 S + 48 Ca has been experimentally studied in a wide energy range, from above the Coulomb barrier down to cross sections in the sub-µb region. The measurements were done at INFN-Laboratori Nazionali di Legnaro, using the 32 S beam from the XTU Tandem accelerator. The excitation function has a smooth behavior below the barrier, and no evident hindrance character shows up in the measured energy region. The fusion barrier distribution has a peculiar shape with two distinct peaks of similar height, lower and higher than the Akyüz-Winther barrier. Coupled-channels calculations using the M3Y + repulsion potential are presented for this system and for 36 S+ 48 Ca. The results of these calculations give a good account of the data, and indicate the influence of one-and two-nucleon transfer channels with positive Q-values, which are only open for 32 S + 48 Ca.

Measurements of fusion-evaporation cross sections for the system 48 Ca + 154 Sm have been performed in the sub-and near-barrier energy range. Barrier-passing cross sections have been obtained by adding recently measured capture-fission cross sections at the same energies, and the barrier distribution for capture has been extracted. The data have been analyzed within a coupled-channel model, and a large subbarrier cross section enhancement is observed, due to the ground state prolate deformation of 154 Sm. The 48 Ca + 154 Sm capture cross sections are compared to existing data on 16 O + 186 W fusion, leading to the same CN, where a few higher-energy points have also been measured. The evaporation residue cross sections for the two systems above the barrier indicate that complete fusion is inhibited for 48 Ca + 154 Sm by ≈40% in that energy region, with respect to 16 O + 186 W.