PARTON EVOLUTION FOR CHEMICAL EQUILIBRATION AT RHIC: DEPENDENCE ON INITIAL CONDITIONS
An important ingredient for studying non-equilibrium evolution of partons at RHIC and LHC is to have physical initial conditions for the partonic system. In this paper we investigate the initial conditions with chemical non-equilibrium at RHIC. Considering the parton production, we studied evolution of the partonic medium with chemical non-equilibrium toward a fully equilibrated partonic system. By using a set of rate equations which describe the chemical equilibration of gluons and quarks, and putting different initial conditions, we obtained the transverse energy production dET/dy and particle multiplicities dN/dy. Comparing the experimental data of dET/dy and dN/dy with numerical results, we get following initial conditions for the formation of partonic system: the initial temperature is around 550 MeV and the initial fugacity λg is from 0.4 to 0.75. It is shown that, until the partonic medium freezes out the partonic system hasn't been totally chemical equilibrated.