Multinucleon transfer channels from Zn70 (15 MeV/nucleon) + Ni64 collisions

In this article, we report a study of ejectile distributions of multinucleon transfer channels from the reaction of 70Zn with 64Ni at 15 MeV/nucleon. The measurements were performed with the MAGNEX large acceptance spectrometer in a wide angular range around the grazing angle and provided high-resolution characterization of the ejectiles in terms of the atomic number Z, the mass number A, the momentum-per-nucleon p/A, and the reaction angle Blab. The momentum distributions, angular distributions, and the production cross sections of several multinucleon transfer channels were extracted and studied in detail. Concerning the production of neutron-rich nuclides, that was one of the main motivations of this work, apart from proton-removal products, neutron-pickup isotopes (with up to three neutrons picked up from the target) were observed. The experimental distributions were compared with two dynamical models, the deep-inelastic transfer (DIT) model and the constrained molecular dynamics (CoMD) model, followed by the deexcitation code GEMINI. The DIT model, designed to describe the sequential exchange of nucleons, offered an overall fair description of the processes involving nucleon exchange, but was unable to describe the quasielastic part of the momentum distributions of several channels, suggesting the presence of direct reaction processes. The microscopic CoMD model gave an overall similar, but less accurate (with respect to DIT) description of the data, indicating that further development is needed. The present work outlines an experimental approach to investigate peripheral collisions of medium-mass heavy ions below the Fermi energy to extract information on the reaction mechanisms and provide guidance for the production of exotic neutron-rich nuclei.