Effect of Inelastic Excitation on Elastic Scattering of Heavy Ions

Abstract

The elastic-scattering angular distribution of 90-MeV $^{18}\mathrm{O}$ on $^{184}\mathrm{W}$ exhibits a dramatic deviation from the typical Fresnel shape, which cannot be reproduced by standard optical-model calculations. The effect, a decrease in the elastic cross section below the Rutherford cross section even at forward angles, is due primarily to Coulomb excitation, and will be even more pronounced for heavier projectiles.