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The directed flow maximum near c_s=0

J. Brachmann·A. Dumitru·H. Stöcker·W. Greiner
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Abstract

We investigate the excitation function of quark-gluon plasma formation and of directed in-plane flow of nucleons in the energy range of the BNL-AGS and for the E(Lab)=40AGeV Pb+Pb collisions performed recently at the CERN-SPS. We employ the three-fluid model with dynamical unification of kinetically equilibrated fluid elements. Within our model with first-order phase transition at high density, droplets of QGP coexisting with hadronic matter are produced already at BNL-AGS energies, E(Lab)=10AGeV. A substantial decrease of the isentropic velocity of sound, however, requires higher energies, E(Lab)=40AGeV. We show the effect on the flow of nucleons in the reaction plane. According to our model calculations, kinematic requirements and EoS effects work hand-in-hand at E(Lab)=40AGeV to allow the observation of the dropping velocity of sound via an increase of the directed flow around midrapidity as compared to top BNL-AGS energy.

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J. Brachmann, A. Dumitru, H. Stöcker, W. Greiner. 2000-08-04. The directed flow maximum near c_s=0. https://doi.org/10.1007/s100500070077

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