Classical and quantum mechanical descriptions of heavy-ion interactions

The discussion of heavy ion interactions between complex nuclei employs classical methods to suggest how the cross section depends on the parameters. Calculations of elastic and inelastic scattering of 18O + 120Sn and the two nucleon transfer reaction 120Sn(18O, 16O) are performed. The latter results are assumed to be typical of multinucleon transfer. The S-matrix structure as function of l is discussed, and, for reactions involving hundreds of angular momenta, a two part approach to the calculation of the S-matrix is suggested. This approach uses quantum mechanics for the region where the nuclear force is dominant and semi-classical or semi-quantal methods for the high l region where smooth behavior of S permits an interpolation between widely spaced l's. (U.S.)