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The fusion cross-sections of $^{126}$Ba, $^{127,126,125}$Cs, $^{125,123,122}$Xe and $^{124,123}$I residues, populated via $x$n, p$x$n, $\alpha$$x$n, and $\alpha$p$x$n channels, have been measured in $^{12}$C+$^{118}$Sn system at E$_{\textrm{lab}}$ $\approx$ 65-85 MeV. For an insight into the formation and decay modes of these residues, experimentally measured cross-sections have been analyzed in the framework of theoretical model codes PACE4 and EMPIRE. 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 and electron capture. 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 $et$ $al.$ and compared with that calculated using theoretical model codes. It has been found that the PACE4 and EMPIRE calculations fairly reproduce the independent cross-sections of evaporation residues within the experimental uncertainties. 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, display negligible contribution of incomplete fusion (ICF). A comparison of incomplete fusion fraction as a function of entrance channel mass-asymmetry for reactions involving $^{12}$C projectile with nearby targets indicates dissimilar behavior of $^{118}$Sn target.

In this work, the cross-sections of 25 fission-like fragments within the mass range 76$\leq$A$\leq$141, expected to be populated via fission of moderately excited compound nucleus produced as a result of complete and/or incomplete fusion in $^{12}$C+$^{208}$Pb reaction at E$_{\rm lab}$ = 81.9 and 75.8 MeV, have been measured using activation technique followed by offline $\gamma$-ray spectroscopy. The yields of different fission-like fragments have been analyzed to generate isotopic and isobaric yield distributions. The value of the mass dispersion parameter, $\sigma^2_A$, is found to be 2.93 and 2.65 for Antimony (Sb) isotope at excitation energy E$^{\star}$ = 45.4 and 39.6 MeV, and 1.24 for Indium (In) isotope at E$^{\star}$ = 45.4 MeV. The charge dispersion parameter $\sigma_Z$ for Sb is estimated to be 0.769 and 0.714 at E$^{\star}$ = 45.4 and 39.6 MeV, respectively. For In isotopes, the value of $\sigma_Z$ is estimated to be 0.430 at E$^{\star}$ = 45.4 MeV. The value of mass and charge dispersion parameters for Sb and In isotopes have been found to be in good agreement with the values reported in the literature for similar systems. The mass distribution of fission-like fragments is found to be fitted with a Gaussian function, except for a few data points, indicating their population via compound nucleus fission. Further, the mass variance ($\sigma^2_M$) displays linear increment with an increase in excitation energy. Two medically important isotopes, $^{99m}$Tc and $^{111}$In, are populated in this system, suggesting a potential formation route.

Excitation functions of several evaporation residues populated via complete and/or incomplete fusion in $^{12}$C+$^{193}$Ir system have been measured at energies $\approx$ 64-84 MeV, and analyzed in the framework of theoretical model code PACE4. It has been found that the $xn$ channels are predominantly populated via complete fusion; however, some of the $pxn$ channels decay via their precursor. A significant enhancement has been observed in the case of $\alpha$-emitting channels over PACE4 calculations, indicating the onset of a reaction mechanism not included in this code, e.g., incomplete fusion. For better insights into the onset and influence of incomplete fusion, the percentage fraction of incomplete fusion has been deduced and analyzed in terms of different entrance-channel parameters. The findings of the present study underline the importance of projectile energy, entrance-channel mass-asymmetry, and the Coulomb factor of interacting partners. The impact of projectile break-up on complete fusion has also been discussed in the framework of the Universal Fusion Function, where suppression of $\approx$ 12$\%$ has been observed in the fusion function. The finding of the present work reinstates that the fusion suppression is affected by the projectile $\alpha$-break-up threshold.

One neutron stripping cross sections ($\sigma_{-1n}$) are measured in $^{9}$Be+$^{159}$Tb system in the energy range E$_{cm}$/V$_{B}$ $\sim$ 0.79 - 1.24 using offline gamma counting technique. The CRC model calculations including the ground state and the 2$^{+}$ resonance state of $^{8}$Be, carried out using the FRESCO code, give a reasonable description of the measured data. In addition, comparisons of reduced 1n-stripping cross sections- $\sigma_{red}$ with $^{9}$Be for different target nuclei (A $\sim$150-200), and $\sigma_{red}$ for $^{9}$Be, $^{6}$Li with $^{159}$Tb target are presented. While no strong target dependence is observed with $^{9}$Be projectile, $\sigma_{red}$($^{9}$Be) is significantly larger than that for $^{6}$Li, which is consistent with the Q-value for transfer reactions and breakup threshold energy of projectiles., Comment: 5 pages, 6 Figures

In this work $\textit{n}$-transfer and incomplete fusion cross sections for $^{9}$Be + $^{197}$Au system are reported over a wide energy range, E$_{c.m.}$ $\approx$ 29-45 MeV. The experiment was carried out using activation technique and off-line gamma counting. The transfer process is found to be the dominant mode as compared to all other reaction channels. Detailed coupled reaction channel (CRC) calculations have been performed for $\textit{n}$-transfer stripping and pickup cross sections. The measured 1$\textit{n}$-stripping cross sections are explained with CRC calculations by including the ground state and the 2$^{+}$ resonance state (E = 3.03 MeV) of $^{8}$Be. The calculations for 1$\textit{n}$-pickup, including only the ground state of $^{10}$Be agree reasonably well with the measured cross sections, while it overpredicts the data at subbarrier energies. For a better insight into the role of projectile structure in the transfer process, a comprehensive analysis of 1$\textit{n}$-stripping reaction has been carried out for various weakly bound projectiles on $^{197}$Au target nucleus. The transfer cross sections scaled with the square of total radius of interacting nuclei show the expected Q-value dependence of 1$\textit{n}$-stripping channel for weakly bound stable projectiles.

To probe the role of the intrinsic structure of the projectile on sub-barrier fusion, measurement of fusion cross sections has been carried out in $^{9}$Be + $^{197}$Au system in the energy range E$_{c.m.}$/V$_B$ $\approx$ 0.82 to 1.16 using off-beam gamma counting method. Measured fusion excitation function has been analyzed in the framework of the coupled-channel approach using CCFULL code. It is observed that the coupled-channel calculations, including couplings to the inelastic state of the target and the first two states of the rotational band built on the ground state of the projectile, provide a very good description of the sub-barrier fusion data. At above barrier energies, the fusion cross section is found to be suppressed by $\approx$ 39(2)\% as compared to the coupled-channel prediction. A comparison of reduced excitation function of $^{9}$Be + $^{197}$Au with other $x$ + $^{197}$Au shows a larger enhancement for $^9$Be in the sub-barrier region amongst Z=2-5 weakly and tightly bound projectiles, which indicates the prominent role of the projectile deformation in addition to the weak binding., Comment: 6 pages, 4 figures, Submitted to Phys. Rev. C

Fusion excitation function of $^{35}$Cl + $^{130}$Te system is measured in the energy range around the Coulomb barrier and analyzed in the framework of the coupled-channels approach. The role of projectile deformation, nuclear structure, and the couplings of inelastic excitations and positive Q$-$value neutron transfer channels in sub-barrier fusion are investigated through the comparison of reduced fusion excitation functions of $^{35,37}$Cl +$^{130}$Te systems. The reduced fusion excitation function of $^{35}$Cl + $^{130}$Te system shows substantial enhancement over $^{37}$Cl + $^{130}$Te system in sub-barrier energy region which is attributed to the presence of positive Q-value neutron transfer channels in $^{35}$Cl + $^{130}$Te system. Findings of this work strongly suggest the importance of +2$n$ - transfer coupling in sub-barrier fusion apart from the simple inclusion of inelastic excitations of interacting partners, and are in stark contrast with the results presented by Kohley \textit{et al.}, [Phys. Rev. Lett. 107, 202701 (2011)]., Comment: 6 pages, 4 figures