DISAPPEARANCE OF THE ISOSPIN DEPENDENCE OF MULTIFRAGMENT PRODUCTION

We present measurements of the multiplicity of charged particles ( ${N}_{c}$) and intermediate mass fragments (IMFs) for ${}^{58}\mathrm{Fe}{+}^{58}\mathrm{Fe}$ and ${}^{58}\mathrm{Ni}{+}^{58}\mathrm{Ni}$ at incident energies of 45 to 105 MeV/nucleon. We find that the neutron-rich system emits more IMFs as a function of ${N}_{c}$ at low incident energies while at the highest energy we observe a much smaller difference between the two systems. Expanding emitting source and statistical multifragmentation simulations reproduce the difference between the two systems at low energies while a charge percolation simulation describes the results at the highest energy.