The evolution of the gluon plasma produced with saturation initial conditions
is calculated via Boltzmann transport theory for nuclear collisions at high
energy. The saturation scale increases with the nuclear size and the beam
energy, and thus we find that the perturbative rescattering rate decreases
relative to the initial longitudinal expansion rate of the plasma. The
effective longitudinal pressure remains significantly below the lattice QCD
pressure until the plasma cools to near the confinement scale. Therefore, the
transverse energy per unit of rapidity and its dependence on beam energy
provides a sensitive test of gluon saturation models: the fractional transverse
energy loss due to final state interactions is smaller and exhibits a weaker
energy dependence than if ideal (nondissipative) hydrodynamics applied
throughout the evolution.Comment: 4 Pages, LaTex, 2 Figures; Contribution to the 15th International
Conference on Ultra-Relativistic Nucleus-Nucleus Collisions (QM 2001), Long
Island, New York, January 15 - 20, 200
