We calculate the baryon flow \langle P _ { x } / A ( y ) \rangle in the energy range from .25 to \leq 2.5 AGeV in a relativistic transport model for Ni + Ni and Au + Au collisions employing various models for the baryon self energies .
We find that to describe the flow data of the FOPI Collaboration the strength of the vector potential has to be reduced at high relative momentum or at high density such that the Schrödinger- equivalent potential at normal nuclear density decreases above 1 GeV relative kinetic energy and approaches zero above 2 GeV .