Effect of projectile structure on break-up fusion for 14N + 175Lu system at intermediate energies

Abstract

In the present work, fusion in heavy-ion collisions at energies near the Coulomb barrier to ≈ 33% above it has been studied for 14N + 175Lu system. The excitation functions of several reaction channels expected to be populated via complete fusion and/or the incomplete fusion of the projectile have been measured. The experimental excitation functions have been critically compared with the predictions of the statistical model code PACE4. The observed enhancement in the measured cross-sections with respect to the theoretical model code PACE4 predictions of all the reactions having α-particle(s) in the exit channel is reminiscent of the fact that incomplete fusion (ICF) is at work in populating these channels besides the complete fusion process. The relative probability of incomplete fusion in fusion dynamics, obtained in terms of incomplete fusion strength function FICF has also been deduced. The observed behavior of FICF suggests the increasing probability of ICF contributions with projectile energy. A strong and a dictating dependence of FICF on projectile structure in terms of its Qα-value has been observed. The reduction procedures for the elimination of the geometric and the static effects suggest that the observed variation in the fusion data has a purely static origin i.e., a manifestation of different potential barriers and radii. The analysis done within the framework of universal fusion function indicates the fusion suppression of ≈ 5% for the 14N + 175Lu system.