Heavy Ion Orbiting and Regge Poles (ii)

We discuss two specific examples of heavy ion orbiting. A first example, α + 16 O at 54.1 MeV reaction dominated by strong optical potentials shows all characteristics of a strongly refractive scattering: Fraunhofer cross over at very forward angles, deep Airy oscillation, rainbow bump, significant increase of the cross section at large angles. We demonstrate semiclassically that this in fact is a typical orbiting reaction. In a second example, α + 28 Si at 18.0 MeV, we describe a special kind of heavy ion orbiting-butterfly scattering, with diffractive oscillations in the entire physical angular range, determined by Regge pole dominance