A relativistic effective interaction for heavy-ion collisions

We present a relativistic effective interaction to be used in a transport-theoretical description of heavy-ion collisions. In contrast to the σ-ω-mean-field model, we have formulated our interaction consistent with the momentum dependence of the real part of the experimentally known nucleon-nucleus optical potential. This is achieved by introducing an additional momentum-dependent scalar and vector potential, similar in structure to an exchange term. Essential features of our approach are energy- and momentum-conservation and thermodynamical consistency. We further present parameter sets for different equations of state which all lead to the proper optical potential. The resulting density dependence of the potentials is compared to microscopic Dirac-Brueckner-Hartree-Fock results. Finally we discuss the details of a transport-theoretical realization. (orig.)