Coulomb And Nuclear Contribution To The Excitation Of Li-7 Incident On Heavy-Nuclei

Measurements are reported for the elastic and inelastic (478 keV excited state) scattering of 68 MeV 7 Li from a 208 Pb target. These are compared with coupled-channels and high-energy adiabatic model calculations, using an alpha-triton cluster structure description of 7 Li. In contrast to the results of fitting to the breakup cross sections, the purely nuclear contributions to the inelastic processes are too small in both models. Inclusion of a Coulomb amplitude in the coupled-channel calculation helps to fit the cross section at angles down to the grazing angle, but is too large at smaller angles. A DWBA Coulomb correction to the adiabatic model improves its ability to fit the data at angles except near grazing.