Comparative study of the radius of sensitivity of the optical model   potentials for $^6$Li+$^{58,64}$Ni and $^{16}$O+$^{58,64}$Ni
  Radii of sensitivity were estimated for the $^{6}$Li+$^{58,64}$Ni system at energies near the Coulomb barrier. For comparison purposes, such radii were also estimated for stable $^{16}$O scattered from same target isotopes. The elastic scattering data were analysed with folded real potential generated from DDM3Y nucleon-nucleon interaction and an imaginary potential of volume Woods-Saxon form. The most sensitive radii for $^{16}$O+$^{58,64}$Ni system are found to be energy independent and close to the strong absorption radius. For $^{6}$Li projectile, unlike its strongly bound counterpart, the crossing radius increases with decreasing energy. However, no two crossing situation has been observed for both $^{6}$Li+$^{58,64}$Ni and $^{16}$O+$^{58,64}$Ni systems at the top of the barrier. 
Mili Biswas