Structure signatures in proton scattering from 9,11Li.

The optical potential and observables for proton-Li elastic scattering are calculated microscopically using the single scattering approximation to the Kerman-McManus-Thaler multiple scattering expansion. The importance of the central and spin-orbit terms of the optical potential, and of the core and halo nucleon contributions, is clarified in terms of the momentum space behaviors of the nucleon-nucleon amplitudes and relevant density distributions. Calculations for the Li and Li systems at 60 and 62 MeV/nucleon, respectively, are compared with the available experimental data and with calculations and data for the proton-He system at similar energy. Three-body models of Li are used. The effects of the halo distribution in Li are clearly manifest in the elastic cross section but there are small differences between observables for structure models with realistic two-neutron asymptotic behaviors. Calculations suggest that the Li core structure is not realistically described by simple models. @S0556-2813~96!05009-1#