Phase transition from hadron gas to quark gluon plasma - influence of the stiffness of the nuclear equation of state

We present a thermodynamically consistent treatment of a density-dependent interaction energy in hadronic matter in a mean-field approximation. With a phenomenological ansatz for this interaction energy we investigate the phase transition between hadronic matter and a quark gluon plasma. We find a strong influence of the stiffness of the nuclear equation of state on the phase transition. The bombarding energies necessary to establish a hadron-to-quark-matter transition are estimated in a one-dimensional hydrodynamical model. (orig.)