Kinetic energy spectra and angular distributions of projectile-like fragments in C12,13+Nb93 reactions

Kinetic-energy spectra and angular distributions of the projectile-like fragments were measured in $^{12,13}\mathrm{C}+^{93}\mathrm{Nb}$ reactions at ${E}_{\mathrm{lab}}=65\phantom{\rule{0.16em}{0ex}}\mathrm{MeV}$ to investigate the reaction mechanisms involving the role of projectile and target structures. It has been observed that one-nucleon pick-up reactions lead to the formation of target-like fragments predominantly in the ground state, whereas nucleon transfer to the target occurs predominantly in the excited states for both $^{12}\mathrm{C}+^{93}\mathrm{Nb}$ and $^{13}\mathrm{C}+^{93}\mathrm{Nb}$ reactions. In the case of $^{93}\mathrm{Nb}(^{12}\mathrm{C}, ^{15}\mathrm{N})^{90}\mathrm{Zr}$ reactions, a significant yield was observed for $^{15}\mathrm{N}$ (``$1p+2n$'' pick-up) indicating the role of the $N=50$ shell in $^{90}\mathrm{Zr}$. Observation of a systematic increase in the forward peaking of the angular distributions of projectile-like fragments with an increasing number of nucleon transfers indicates an increase in the projectile-target overlap with increasing mass transfer. Angular distributions for inelastic scattering as well as transfer channels populating various states of projectile-like fragments and/or target-like fragments were calculated simultaneously by using the coupled reaction channels code fresco and were in reasonable agreement with the experimental data. New (modified) spectroscopic amplitudes have been proposed for some of the unknown (known) overlapping states for calculating transfer cross sections. In the case of $^{13}\mathrm{C}+^{93}\mathrm{Nb}$, the transfer channels corresponding to ``$2n$'' and ``$1p+1n$'' pick-up channels were not observed. This may be due to the higher N/Z ratio of the projectile, highlighting the importance of projectile structure in addition to that of the target.