Isospin Distillation with Radial Flow: a Test of the Nuclear Symmetry Energy

We discuss mechanisms related to isospin transport in central collisions between neutron-rich systems at Fermi energies. A fully consistent study of the isospin distillation and expansion dynamics in two-component systems is presented in the framework of a stochastic transport theory. We analyze correlations between fragment observables, focusing on the study of the average N/Z of fragments, as a function of their kinetic energy. We identify an EOS-dependent relation between these observables, allowing to better characterize the fragmentation path and to access new information on the low density behavior of the symmetry energy.