Isospin influence on the intermediate-Mass Fragments production at low energy

We studied isotropization and thermalization of the quark-gluon plasma produced by decaying color-electric flux tubes created at the very early stages of relativistic heavy ion collisions. We coupled the dynamical evolution of the initial field, which decays to a plasma by the Schwinger mechanism, to the dynamics of the many particles system produced by the decay. The evolution of such a system is described by relativistic transport theory at fixed values of the viscosity over entropy density ratio. Within a single self-consistent calculation scheme we computed quantities which serve as indicators of the equilibration of the plasma for a 1+1 dimensional expanding geometry. We find that the initial color-electric field decays within 1 fm/c and particles production occurs in less than 1 fm/c; however, in the case of large viscosity oscillations of the field appear along the entire time evolution of the system, affecting also the behaviour of the ratio between longitudinal and transverse pressure. In case of sma

The reactions 78 Kr + 40 Ca and 86 Kr + 48 Ca realized at 10 AMeV, have been studied in Catania at LNS with the 4π multidetector CHIMERA. For these systems, we have already studied the fusion-evaporation and fission-like processes. Now we will present a study of the break-up of the Projectile-Like Fragment (PLF) into two fragments, following more violent deep-inelastic collision. A selection method has been developed, in order to discriminate PLF break-up from events due to other mechanisms, fusion-fission-like processes, which populate the same region of the phase-space. A preference for PLF aligned break-up, along the direction of the PLF-TLF separation axis with the light fragment emitted in the backward part, has been evidenced, suggesting dynamical-nonequilibrium effects. The isospin is expected to play a crucial role in the onset of this process; a comparison between the neutron-rich 86 Kr + 48 Ca system and neutron-poor 78 Kr + 40 Ca one will be presented.