The neutron content of compound nuclei (CN), formed in low-energy nuclear reactions, manifests itself in the magnitude of the fragment cross sections. These days, the study of the dependence of associated decay channels on the neutron content is an attractive topic due to the worldwide availability of radioactive ion beams. The dynamical cluster-decay model (DCM) is used to analyze the decay of an isotopic chain of CN ${}^{58–61}\mathrm{Cu}^{*}$, formed in the reactions ${}^{35}\mathrm{Cl}+{}^{23–26}\mathrm{Mg}$, respectively, at different center-of-mass energies $E_{\mathrm{c}}.\mathrm{m}.$. The DCM's collective clusterization approach, based on quantum mechanical fragmentation theory, is employed to understand the influence of successive neutron addition on the decay modes of these CN into light particles (LPs; $A\le 4$), intermediate mass fragments (IMFs; with $5\le A\le 20$), and symmetric mass fragments [SMFs; ($A_{\mathrm{CN}}/2)\pm 10$], and the mutual competition between them. We see that adding a neutron changes the potential energy surfaces (PESs), and, consequently, the preformation profiles of the CN change significantly from ${}^{58}\mathrm{Cu}^{*}$ to ${}^{61}\mathrm{Cu}^{*}$. The PESs for all the CN show that LPs remain dominant in the decay process with their highly minimized values at all the angular momentum $\ell$ values, with IMFs following closely, particularly light IMFs (LIMFs; $5\le A\le 12$). The combined results of the preformation and penetration processes yield fusion cross-section values for the given decays of LPs, IMFs, and SMFs. We find that LPs and LIMFs are the most significant decay modes, with the former being chased by the latter consistently with the successive addition of a neutron in CN from ${}^{58}\mathrm{Cu}^{*}$ to ${}^{60}\mathrm{Cu}^{*}$ and superseding it for the compound nucleus ${}^{61}\mathrm{Cu}^{*}$. The DCM-calculated fusion cross sections ${\sigma }_{\mathrm{fus}}^{\mathrm{DCM}}$ are given by the sum of LP cross sections (${\sigma }_{\mathrm{LP}}$) and LIMF cross sections (${\sigma }_{\mathrm{LIMF}}$), which are in good comparison with the given experimental data. It is important to mention here that $\mathrm{\Delta }R$, associated with the barrier-lowering phenomenon, shows a linear relationship with the $E_{\mathrm{c}}.\mathrm{m}.$ values.

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• Cluster models
• Fission
• Low & intermediate energy heavy-ion reactions
• Nuclear decay
• Nuclear fragmentation
• Nuclear fusion
• Nuclear reactions