Abstract:
In the present work, excitation functions of several reaction residues in the
system 19F+169Tm, populated via the complete and incomplete fusion processes, have been measured using off-line γ-ray spectroscopy. The analysis of
excitation functions has been done within the framework of statistical model
code PACE4. The excitation functions of residues populated via xn and pxn
channels are found to be in good agreement with those estimated by the
theoretical model code, which confirms the production of these residues solely
via complete fusion process. However, a significant enhancement has been
observed in the cross-sections of residues involving α-emitting channels as
compared to the theoretical predictions. The observed enhancement in the
cross-sections has been attributed to the incomplete fusion processes. In order
to have a better insight into the onset and strength of incomplete fusion, the
incomplete fusion strength function has been deduced. At present, there is no
theoretical model available which can satisfactorily explain the incomplete
fusion reaction data at energies ≈4–6 MeV/nucleon. In the present work, the
influence of incomplete fusion on complete fusion in the 19F+169Tm system
has also been studied. The measured cross-section data may be important for
the development of reactor technology as well. It has been found that the incomplete fusion strength function strongly depends on the α-Q value of the
projectile, which is found to be in good agreement with the existing literature
data. The analysis strongly supports the projectile-dependent mass-asymmetry
systematics. In order to study the influence of Coulomb effect (Z ZP T) on
incomplete fusion, the deduced strength function for the present work is
compared with the nearby projectile–target combinations. The incomplete
fusion strength function is found to increase linearly with Z ZP T, indicating a
strong influence of Coulomb effect in the incomplete fusion reactions.
