Investigation of incomplete fusion dynamics at energy 4–8 MeV/nucleon

Abstract

The recoil-catcher activation technique followed by the offline γ-ray spectroscopy has been adopted for the excitation function measurement of residues populated in 12,13C induced reactions with 175Lu target at lower projectile energies ≈4–8 MeV/nucleon. The independent cross-sections for some of the populated residues have been estimated by subtracting the contributions of higher charge precursor isobars from the measured cumulative cross-sections. The measured excitation functions are compared with theoretical predictions based on statistical model code PACE-4. This comparison reveals that complete fusion process solely contributes in the formation of xn-pxn channels and an enhancement in the measured cross-sections of α-emitting channels from the theoretical predictions may be attributed to the incomplete fusion process. The incomplete fusion probability is found to be higher in case of C12 than for a one neutron rich projectile C13 throughout the incident energy region. Present findings obtained for 12,13C + 175Lu systems have been compared with informations extracted from previously studied systems and projectile structure is found to strongly affect the incomplete fusion dynamics in terms of projectile α-Q-value along with projectile-target mass-asymmetry. Moreover, it may be pointed out that Morgenstern's mass-asymmetry systematic is probably the projectile structure dependent systematic. A substantial contribution to incomplete fusion coming from collision trajectories with ℓ≤ℓcrit is also observed, contrary to the SUMRULE model assumptions.