Phase Structure of QCD Matter in a Chiral Effective Model with Quarks

Philip Rau; Jan Steinheimer; Stefan Schramm

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arXiv · 1308.4518

Phase Structure of QCD Matter in a Chiral Effective Model with Quarks

Philip Rau·Jan Steinheimer·Stefan Schramm

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Abstract

Using a unified hadron-quark effective model for the QCD equation of state, this paper studies the phase structure of strongly interacting matter in a wide range of temperature and baryonchemical potential. At small potentials the model yields a smooth cross-over to chirally restored matter with a transition temperature and curvature in line with recent lattice QCD estimates and thermal model fits of freeze-out curves. Trajectories of constant entropy per net baryon number show a clear dependence on the particle composition in the model and on repulsive vector field interactions. Although the model might feature a critical end-point at a rather high baryonchemical potential and low temperature, probing it in heavy-ion collisions might be highly challenging due to a large thermodynamic spread of matter in the collision fireball.

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Philip Rau, Jan Steinheimer, Stefan Schramm. 2013-08-21. Phase Structure of QCD Matter in a Chiral Effective Model with Quarks. https://arxiv.org/abs/1308.4518

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