The strengths of resonances located at center-of-mass energies of E c.m. = 189, 304, 374, and 418 keV for the 25 Mg(p,γ ) reaction have been measured for the first time with an off-line method: Mg targets were firstly activated with protons at the resonance energies and the produced 26 Al g nuclei were counted by means of highly sensitive accelerator mass spectrometry (AMS). Thus, the production of 26 Al in its ground state is determined independently from the γ -decay branching ratio. While the 304, 374, and 418 keV resonances show fair agreement with previous measurements, the 189 keV resonance yield a significantly less strength. In addition, an experimental upper limit for the E c.m. = 92 keV resonance was determined.

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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