Interpretation of Airy minima in 16O+16O and 16O+12C elastic scattering in terms of a barrier-wave/internal-wave decomposition

The observation of refractive effects in O-16 + O-16 and O-16 + C-12 elastic scattering data has definitively established the fact that the optical potential for sortie light heavy-ion systems is relatively transparent and that its real part is deep. Most of the interpretations of the rainbow features of these data rely on the so-called nearside-farside decomposition of the scattering amplitude. Starting from recent optical model analyses of O-16 + O-16 and O-16 + C-12 elastic scattering around 100 MeV incident energy as all example, we present an alternative interpretation based oil the barrier-wave/internal-wave decomposition first proposed by Brink and Takigawa. This method, which complements the nearside-farside approach, demonstrates clearly the exceptional transparency of the O-16 + O-16, and to a lesser extent O-16 + C-12, interactions at the investigated energies and makes possible the extraction of the two contributions whose interference explains the Airy oscillations seen in the farside amplitude. (C) 2002 MAIK "Nauka/Interperiodica".