PREEQUILIBRIUM EVOLUTION OF QUARK-GLUON PLASMA

We study the production and the evolution of quark-gluon plasma expect ed to be formed in ultrarelativistic heavy-ion collisions, within the color flux-tube model. We introduce the gluonic component in the Boltz mann equation, which we solve in the phase space which is extended to include the SU(3) color degree of freedom. The color degree of freedom is shown to play a decisive role in equilibration, and in fixing the temperature of the plasma. We further find that the soft partons that we study here contribute substantially to the bulk properties. Finally , the model is shown to provide a detailed picture of how the quark-gl uon plasma evolves and is driven towards a hydrodynamic flow, which st arts occurring around 1 fm.