Comprehensive study of the d + Au 197 system at near-barrier energies

Abstract

We present experimental data on the most relevant reaction channels of the d + 197Au system. The angular distribution for neutron transfer (pickup and stripping) and breakup protons were obtained by the online detection of charged particles with two fourfold-∆E silicon telescopes. Additionally,integral cross sections for fusion-evaporation and neutron transfer were obtained by the offline detection of β-delayed γ-rays with a HPGe detector. Offline and online methods for neutron transfer give compatible and complementary results.The angular distributions obtained for the n-pickup and n-stripping are fairly reproducedby coupled reaction channel calculations, although limited model spaces are adopted and thespectroscopic amplitudes are assumed on the basis of qualitative argument, which considered known excited states of 196Au up to around 700 keV. To describe the n-stripping process populating states around 4.3 MeV of 198Au excitation energy, compatible with the optimum value for the process Qopt = 0, a series of states in 198Au was assumed for the calculation. The inclusive experimental breakup cross section was fairly well described using the Ichimura-Austern-Vincent (IAV) formalism.Suppression of the complete fusion cross section above the Coulomb barrier was observed, being 45% of the one-channel calculation; for energies below the barrier, the possible enhancement can not be concluded. The sum of the cross section of these channels is compatible with the reaction cross section derived from the elastic scattering fits already published for this same system.