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

摘要

The quantum mechanical fragmentation theory (QMFT)-based dynamical cluster-decay model (DCM) has been applied to predict the fusion cross section (sigma(fus)) for the compound systems (CS) Zn-60*, Ni-60* and( 60)Fe* formed, respectively, via He-4+ Ni-56, He-4+Fe-56 and He-4+Cr-56, reactions, by fixing the only parameter (neck length Delta R-emp) of the model, empirically with the available experimental data on sigma(fus) of Ti-44,Ti-48* and( 68)Ge* formed through He-4 induced reactions at different incident energies, i.e., E-l(ab) similar to 10, 13, 17 MeV. We have investigated the effect of neutron to proton (N I Z) ratio in the decay of CS under study, i.e.,(60)zn*, Ni-60* and Fe-60*. The contributions of light-particles cross section (sigma(LPs)), intermediate mass fragments cross section (sigma(IMFs)) and symmetric mass fragments cross section (sigma(SMFs)) are taken together to calculate sigma(f)(us) (= sigma(LPs) + sigma(IMFs) + sigma(SMFs)). The small contribution of SMFs is seen in sigma(f)(us), 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 (P-0) 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 Zn-60* having N = Z, the LPs, IMFs and SMFs yields increasing with increase in incident energy. (C) 2018 Elsevier B.V. All rights reserved.