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Measurements of fusion-evaporation cross-sections for the system Ca-48 + Sm-154 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 Sm-154. The Ca-48 + Sm-154 capture cross-sections are compared to existing data on O-16 + W-186 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 Ca-48 + Sm-154 by approximate to 40% in that energ, region, with respect to O-16 + W-186.

Recent experimental data on relatively mass-asymmetric collisions show that fusion hindrance can be explained in terms of the onset of quasi-fission reactions. The influence of mass-asymmetry, shell effects and target deformation on such phenomena is presented and possible implications for super-heavy element production are discussed.

The magnetic spectrometer Prisma for heavy ions, at the Laboratori Nazionali di Legnaro, is a device with large acceptance and good resolution. Installation of the spectrometer and its detectors has been recently completed. Preliminary results of the first measurements on multinucleon transfer reactions are reported.

Heavy-ion transfer reactions at energies close to the Coulomb barrier are complex in their nature and it is important to identify the relevant degrees of freedom which have to be included in the description of the reaction mechanism. In different studied systems the main degrees of freedom in the quasi-elastic regime are reported to be single nucleon transfers, i.e. the multinucleon transfer channels are mostly populated via a sequance of single particles. Enhancement of two nucleaon transfer channels with respect to estimated probabilities for independent particle transfers are often discussed in literature, but the reported studies are mostly based on purely phenomenological ground.

We report on the measurement of subbarrier fusion cross sections for ^48Ca+^90Zr, ^96Zr, with the aim to pin down the contribution of transfer and inelastic excitations in reactions involving ^90Zr and ^96Zr. We also present a re-evaluation of previously published data.