Directed Flow in 158 AGeV 208 Pb + 208 Pb Collisions.

Pb collisions.A directed flow analysis of the rapidity dependence of the average transverse momentum projectedonto the reaction plane is presented for semi-central collisions with impact parameters ≈8 fm, wherethe flow effect is largest. The magnitude of the directed flow is found to be significantly smallerthan observed at AGS energies and than RQMD model predictions.25.75.-q,25.75.Ld,25.75.Dw