Direct versus sequential four-particle transfer in heavy ion collisions with superfluid nuclei: Sn+Sn reaction

Abstract

The direct transfer of four nucleons in reactions with superfluid systems is compared with the feeding of the same final channel by a successive transfer of correlated nucleon pairs. A quantitative analysis is carried out for the reaction 120Sn+112Sn which shows the overwhelming dominance of the direct multiparticle transfer at bombarding energies below the Coulomb barrier. Results of simple estimates supplemented by full coupled-channel calculations provide orientation for selecting the experimental conditions which best exhibit the specific characteristics of the superconductive phase. The possibility of detecting an interference pattern between the two processes is also discussed.