Nuclear Physics A 672 (2000) 387–416 www.elsevier.nl/locate/npe Study of diffractive and refractive structure in the elastic 16 O+ 16 O scattering at incident energies ranging from 124 to 1120 MeV ✩ Dao T. Khoa a,b , W. von Oertzen a,1 , H.G. Bohlen a,∗ F. Nuoffer c a Hahn-Meitner-Institut GmbH, Glienicker Str. 100, D-14109 Berlin, Germany b Institute for Nuclear Science & Technique, VAEC, P.O. Box 5T-160, Nghia Do, Hanoi, Viet Nam c Physikalisches Institut, Universität Tübingen, Auf der Morgenstelle 14, D-72076 Tübingen, Germany Received 26 November 1999; accepted 22 December 1999 Abstract The experimental data on elastic 16 O+ 16 O scattering at incident energies ranging from 124 to 1120 MeV have been analyzed within the standard optical model (OM), using either the phenomenological (Woods-Saxon squared) potential or that calculated within the double-folding model for the real part of the optical potential. Structure of the elastic cross sections at smallest scattering angles was found to be of a pure diffractive nature, which enabled a consistent check of the absolute normalization of the elastic data under study. The OM analysis shows unambiguously the evolution of the refractive scattering pattern in the 16 O+ 16 O system over this energy range. The large angle region of the data is dominated by the refractive far-side scattering. The oscillating Airy structure can be consistently described by a set of optical potentials with the real part given by the folding model and a weak absorptive imaginary potential.  2000 Elsevier Science B.V. All rights reserved. PACS: 25.70.Bc; 24.10.Ht; 21.30.Fe Keywords: 16 O+ 16 O elastic scattering; Airy minima; Nuclear rainbow 1. Introduction In recent years, our knowledge of the interaction between heavy-ions (HI) has been broadened significantly, especially through studies of elastic scattering of certain combinations of light heavy-ions, for which the absorption is relatively weak and refractive effects appear. Refractive (rainbow) phenomena in nuclear scattering provide a unique ✩ Research supported, in part, by the Alexander von Humboldt-Stiftung of Germany. ∗ Corresponding author. E-mail: bohlen@hmi.de 1 Also Fachbereich Physik, Freie Universität Berlin. 0375-9474/00/$ – see front matter  2000 Elsevier Science B.V. All rights reserved. PII:S0375-9474(99)00856-8