Starting from a semiphenomenological analysis of the ${}^{16}{\mathrm{O}+}^{208}\mathrm{Pb}$ elastic scattering data at energies ranging from 78 to 312.6 MeV and using the dispersion relation, we have obtained the energy dependence of the real potential up to 1503 MeV. This real potential was then used with an absorptive potential calculated with a microscopic model, to analyze the elastic scattering at 793 and 1503 MeV. A good agreement between calculated and measured elastic scattering cross sections at 793 MeV corroborates that at this energy the collision is still dominated by collective processes. However, at 1503 MeV, the agreement between theoretical calculations and experiment is poor as expected, showing that the low collective modes are not the “preponderant” channels responsible for absorption anymore.

• Received 16 April 1999

DOI:https://doi.org/10.1103/PhysRevC.60.034612