Reaction mechanism of heavy-ion charge-exchange scattering at intermediate energies

The reaction mechanism of heavy-ion charge-exchange scattering at low and intermediate incident energies is studied theoretically. Contributions of direct charge exchange due to central and tensor isovector interactions and of charge exchange via sequential proton and neutron transfer are taken into account in one-step and two-step exact-finite-range distorted-wave Born-approximation calculations. The nuclear structure of the intermediate and final states is described within the shell model. Calculations for ${}_{}{}^{12}{}_{}{}^{}$C${(}^{12}$C, ${}_{}{}^{12}{}_{}{}^{}$N${)}^{12}$B2 indicate that direct charge exchange is safely dominant for incident energies E/A≳100 MeV.