Mechanism of the quasi-elastic scattering based on the dinuclear system concept

A unified description of full reaction channels in low-energy heavy-ion collisions is a great challenge. Although the theoretical models based on the dinuclear system (DNS) concept have been successfully employed in multinucleon transfer (MNT) reactions, the underestimation of the quasi-elastic (QE) channel results in unreliable description of few nucleon transfer, especially for the light reaction systems. In this work, the DNS-sysu model is improved by introducing the impact-parameter-dependent transition probabilities for a unified description of few nucleon and many nucleon transfer in MNT reactions. Extensive experimental data -- including reactions such as 40Ca, 58Ni, 64Ni, 136Xe, and 208Pb + 208Pb -- were compared with the model predictions. The calculated isotopic distributions, mass distributions, and charge distributions show good agreement with experimental measurements. The improved DNS-sysu model enables reasonable characterization and description of the QE/grazing collisions, notably resolving long-standing underestimation in the QE channel.