The delayed x-ray detection technique was used to measure complete and incomplete fusion cross sections for the 9 Be + 144 Sm reaction at sub-and near-barrier energies. Elastic and inelastic scattering for this system were also measured. Reaction cross sections were derived and the transfer cross sections of one neutron were calculated. The suppression of complete fusion above the barrier, of the order of 10%, is attributed to 9 Be breakup and is considerably smaller than the value of 30% found for the 9 Be + 208 Pb system.

We study the behavior of the fusion, break-up, reaction and elastic scattering of different projectiles on 64 Zn, at near and above barrier energies. We present fusion and elastic scattering data with the tightly bound 16 O and the stable weakly bound 6 Li, 7 Li and 9 Be projectiles. The data were analyzed by coupled channel calculations. The total fusion cross sections for these systems are not affected by the break-up process at energies above the barrier. The elastic (non-capture) break-up cross section is important at energies close and above the Coulomb barrier and increases the reaction cross sections. In addition we also show that the break-up process at near and sub-barrier energies is responsible for the vanishing of the usual threshold anomaly of the optical potential and give rise to a new type of anomaly.

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Fusion cross sections have been measured for ' 0+ ' ' Sm at bombarding energies in the range 61 MeV~E&, . b(' 0)~75 MeV by o6'-line observation of x rays emitted in the radioactive decay of Yb isotopes and their daughters. The fusion excitation functions are similar to those of the adjacent even Sm isotopes. It appears, therefore, that the odd valence neutrons do not have any unusual inhuence on the subbarrier enhancement of o. f", in these systems. The x-n distributions of the evaporation residues were also determined. The nuclear deformation parameters P2 deduced for the odd and even Sm isotopes using Wong s model establish a smooth systematic behavior of P2 with target collectivity. Fusion cross sections for ' 0 with all the stable Sm isotopes are tabulated.