Study of α-induced reactions forming A = 60 compound systems within dynamical cluster-decay model

The quantum mechanical fragmentation theory (QMFT)-based dynamical cluster-decay model (DCM) has been applied to predict the fusion cross section (σfus) for the compound systems (CS) 60Zn⁎, 60Ni⁎ and 60Fe⁎ formed, respectively, via 4He+56Ni, 4He+56Fe and 4He+56Cr, reactions, by fixing the only parameter (neck length ΔRemp) of the model, empirically with the available experimental data on σfus of 44,48Ti⁎ and 68Ge⁎ formed through 4He induced reactions at different incident energies, i.e., Elab∼ 10, 13, 17 MeV. We have investigated the effect of neutron to proton (N/Z) ratio in the decay of CS under study, i.e., 60Zn⁎, 60Ni⁎ and 60Fe⁎. The contributions of light-particles cross section (σLPs), intermediate mass fragments cross section (σIMFs) and symmetric mass fragments cross section (σSMFs) are taken together to calculate σfus (=σLPs+σIMFs+σSMFs). The small contribution of SMFs is seen in σfus, the contributions of LPs and IMFs yields being much more prominent, for the decay of all CS under study at different incident energies. We see that the preformation probability (P0) and penetrability (P) for SMFs decrease with increase in the value of N/Z ratio, and hence the symmetric breakup drops-out-of-favor for higher N/Z values. In other words, the symmetric mass decay is favored in the case of 60Zn⁎ having N=Z, the LPs, IMFs and SMFs yields increasing with increase in incident energy.