We discuss a model for the energy distribution and the early space-time
evolution of a heavy ion collision. We estimate the gluon field generated in
the wake of hard processes and through primordial fluctuations of the color
charges in the nuclei. Without specifying the dynamical mechanism of
thermalization we calculate the energy momentum tensor of the following plasma
phase. The results of this model can be used as initial conditions for a
further hydrodynamic evolution.Comment: Contribution to Quark Matter 2005; 4 pages, 4 figure