The directed flow maximum near c_s=0
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.
Keywords
Cite
@article{arxiv.nucl-th/9912014,
title = {The directed flow maximum near c_s=0},
author = {J. Brachmann and A. Dumitru and H. Stöcker and W. Greiner},
journal= {arXiv preprint arXiv:nucl-th/9912014},
year = {2009}
}
Comments
10 pages, 4 figures; plot of p(e) at various specific entropies shows why mixed phase is not soft at AGS energy