T. Krogulski

HOW MANY FUSION BARRIERS

Fusion barrier distributions for the 20Ne + 112,116,118Sn systems have been extracted from quasi-elastic scattering cross sections measured at the Warsaw HIL Cyclotron. Results are compared to coupled-channels calculations performed with the CCFULL code. The overall widths of the distributions are reproduced on taking account of the low-lying collective states of the target and projectile but some puzzling discrepancies in their shapes remain to be explained.

FUSION BARRIER DISTRIBUTIONS IN 20,22Ne+natNi

Barriers height distributions for 20,22Ne on natNi have been measured using quasi-elastic scattering at backward angles. The results have been compared to coupled-channels calculations performed with the CCQUEL code. A fair agreement with data has been obtained if the values of a hexadecapole deformation parameters of 20Ne and 22Ne are reduced by a factor of 2 with respect to their previously quoted values.

STRUCTURE OF BARRIER DISTRIBUTIONS: PROBING THE ROLE OF NEUTRON-TRANSFER CHANNELS

In view of its large deformation, which should give rise to strong barrier structures, the 20Ne projectile has been used to study the influence of neutron-transfer channels on the distribution of barrier heights. A previous experiment with a combination of projectiles 20,22Ne suggested that the role of α-particle transfer channels is small. By an appropriate choice of targets (90Zr and 92Zr), having very similar intrinsic structures (excited states and deformation parameters) but giving rise to different Q-values for neutron transfers, we highlight the role of these channels.