Isoscaling in central 124Sn+64Ni, 112Sn+58Ni collisions at 35 AMeV

124Sn+64Ni and 112Sn+58Ni reactions at 35 A MeV incident energy were studied by using the 688 Si-CsI telescopes of the forward part (1°≤θ lab ≤30°) of CHIMERA multi-detector. The most central part, 1% of the total measured cross section was selected by means of a multidimensional analysis of the experimental observables. The detected isotopes of light fragments (3≤Z≤8) provided information on breakup temperatures of the emitting sources. The space-time structure of these sources was deduced from fragment correlations. An odd-even effect in the fragment production, enhanced by the isospin of the entrance channel, was observed. Freeze-out unbound neutron-to-proton relative densities for both studied reactions have been deduced, indicating for a possible isospin distillation mechanism related to a phenomenon of the liquid-gas phase transition in asymmetric systems. © 2003 Elsevier B.V. All rights reserved.