The 12C+24Mg elastic scattering:. An example of anomalous transparency at Coulomb barrier energies

Fifteen complete angular distributions of the elastic scattering of 12C+24Mg were measured at energies around the Coulomb barrier (Ecm=10.67-16 MeV). The angular distributions are strongly oscillating and could be well described by an optical potential family, whose real part was determined without continuous ambiguity. The imaginary part of this optical potential is very shallow. At four energies the inelastic scattering angular distributions leading to the 2+ state of the 24Mg were also measured and analysed with coupled-channel calculations. The volume integrals of the optical potentials used in the coupled-channel calculations present the threshold anomaly in their energy dependence, with a clear Q-value dependence. (orig.)