Speaker
Description
Different decay modes of complete/incomplete fusion and pre-equilibrium have been investigated in $^{12}$C+$^{118}$Sn system. The channel-by-channel fusion cross-sections of $^{126}$Ba ($4$n), $^{127,126,125}$Cs (p$x$n), $^{125,123,122}$Xe ($\alpha$$x$n) and $^{124,123}$I ($\alpha$p$x$n) residues have been measured at E$_{\textrm{lab}}$ $\approx$ 65-85 MeV [1]. Experimentally measured cross-sections have been analyzed in the framework of theoretical model codes PACE4 and EMPIRE. In this work, The cross-sections of p$x$n ($^{127,126,125}$Cs), $\alpha$xn ($^{125}$Xe), and $\alpha$p$x$n ($^{123}$I) channels have been found to be substantially fed from their higher charge isobars via $\beta^+$ decay/EC. In order to deduce the contribution of higher charge isobars in the population of these residues, the independent cross-sections of evaporation residues have been calculated using the prescription of Cavinato et al.[2] and compared with theoretical model codes. It has been found that the PACE4 and EMPIRE calculations fairly reproduce the independent cross-sections of evaporation residues.
Interestingly, it has been found that the $\alpha$-emitting channels, contrary to established findings in reactions involving $\alpha$-cluster projectiles (e.g., $^{12}$C, $^{16}$O, etc.) at low incident energies, shows zero, or negligible contribution from incomplete fusion. To validate the findings of the excitation functions, forward ranges of recoils for reactions $^{118}$Sn($^{12}$C,$x$n), $^{118}$Sn($^{12}$C,p$x$n), $^{118}$Sn($^{12}$C,$\alpha$xn) and $^{118}$Sn($^{12}$C,$\alpha$p$x$n) have been measured at beam energy of E$_{\textrm{lab}}$ $\approx$ 78.9 MeV. This disentangles different processes in $^{12}$C + $^{118}$Sn system by analyzing full and partial linear momentum transfer, and presents the relative contributions of compound nucleus, reduced compound nucleus and precompound processes. Experimental data and its analysis suggest unique behavior of this system. Detained results will be presented during the conference.
[1] Priyanka et al., Phys. Rev. C. (under review) https://arxiv.org/abs/2410.03691
[2] M. Cavinato, E. Fabrici, E. Gadioli, E. G. Erba, P. Vergani, M. Crippa, G. Colombo, I. Redaelli, and M. Ripamonti, Phys. Rev. C 52, 2577 (1995).
