Abstract
Exclusive measurements of prompt gamma-rays from the heavy-residues with various light charged particles in the Li-7 + Pt-198 system, at an energy near the Coulomb barrier (E/V-b similar to 1.6) are reported. Recent dynamic classical trajectory calculations, constrained by the measured fusion, alpha- and t-capture cross-sections have been used to explain the excitation energy dependence of the residue cross-sections. These calculations distinctly illustrate a two-step process, breakup followed by fusion, in case of the capture of t and alpha clusters; whereas for He-6+p and He-5+d configurations, massive transfer is inferred to be the dominant mechanism. The present work clearly demonstrates the role played by the cluster structures of Li-7 in understanding the reaction dynamics at energies around the Coulomb barrier. (C) 2012 Elsevier B.V. All rights reserved.