Atomic effects in heavy-ion elastic scattering

Angular distributions of a 208Pb beam on 208Pb thin targets at very small angles were measured. The shape of the experimental distribution is not Gaussian, indicating a plural scattering regime rather than multiple scattering. The distribution was well reproduced by a Monte Carlo simulation of the straggling process. For the first time we observed and quantified the influence of the production of electrons during the scattering. This effect was observed in the angular correlation of the scattered 208Pb nuclei detected in kinematic coincidence and also in the limiting angle of the 208Pb scattered in a 107,109Ag target. This effect introduces a spread in the scattered angle which is of the same order of magnitude as the angular straggling. copyright 1997 The American Physical Society