FURTHER-STUDIES OF THE EQUILIBRATION PROCESS IN RELATIVISTIC HEAVY-ION COLLISIONS

The local equilibration process is studied with the relativistic Boltz mann-Uehling-Uhlenbeck model. Both the local ratio of the mean pperpen dicular-to to the mean pparallel-to and the local ratio of the energy of random motion to that of the collective motion for relativistic hea vy-ion collisions are studied. The effect of the equation of state on the reaction dynamics is studied systematically. The mass dependence o f the degree of the equilibrium is also studied. The calculation resul ts show that in the centre zone of the reaction the baryons reach a co nsiderable degree of equilibrium but not in the outer zones. Thus the concept based on the complete local equilibrium should be used careful y.