Effect of secondary decay on isoscaling: Results from the canonical thermodynamical model

The projectile fragmentation reactions using $^{58}Ni$ $\&$ $^{64}Ni$ beams at 140 MeV/n on targets$^{9}Be$ $\&$ $^{181}Ta$ are studied using the canonical thermodynamical model coupled with an evaporation code. The isoscaling property of the fragments produced is studied using both the primary and the secondary fragments and it is observed that the secondary fragments also respect isoscaling though the isoscaling parameters $\alpha$ and $\beta$ changes. The temperature needed to reproduce experimental data with the secondary fragments is less than that needed with the primary ones. The canonical model coupled with the evaporation code successfully explains the experimental data for isoscaling for the projectile fragmentation reactions.