Effect of neutron excess in the entrance channel on the O 18 + Nb 93 system: An experimental study relevant to incomplete-fusion dynamics

The incomplete fusion dynamics in the O18+Nb93 system at energies above the Coulomb barrier has been investigated. The experimentally measured cross sections have been compared with the theoretical predictions of the statistical model code pace4. To examine the effect of entrance channel parameters on the onset and strength of incomplete fusion, relative contributions of complete and incomplete fusion have been deduced from the analysis of measured excitation functions. The contribution of incomplete fusion deduced from the analysis of excitation functions has been studied in terms of various entrance channel parameters, namely, entrance channel mass asymmetry (μA) of interacting projectile and target combination, Coulomb factor (ZPZT), ground state α-Q value of the reaction, and neutron skin thickness of target nuclei. It has been found that the probability of incomplete fusion depends strongly on entrance channel parameters. Further, the incomplete fusion contribution for the O18 projectile with two excess neutrons is noticed to be relatively larger as compared to O16. This may be due to the larger probability of breakup for the O18 projectile resulting in rather weak binding forces as compared to O16. The existence of incomplete fusion below critical angular momentum (ℓcrit), i.e., ℓ≤ℓcrit, has also been observed for the studied system.