Fluid dynamics near the QCD critical point

Marcus Bleicher; Christoph Herold

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arXiv · 1303.3686

Fluid dynamics near the QCD critical point

Marcus Bleicher·Christoph Herold

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Abstract

We present a fully dynamical model to study the chiral and deconfinement transition of QCD simultaneously. The quark degrees of freedom constitute a heat bath in local equilibrium for both order parameters, the sigma field and a dynamical Polyakov loop. The nonequilibrium evolution of these fields is described by Langevin equations including dissipation and noise. In several quench scenarios we are able to observe a delay in the relaxation times near the transition temperature for a critical point as well as a first-order phase transition scenario. During the hydrodynamical expansion of a hot quark fluid we find a strong enhancement of thermal fluctuations at the first-order transition compared to a scenario with a critical point.

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Marcus Bleicher, Christoph Herold. 2013-03-15. Fluid dynamics near the QCD critical point. https://arxiv.org/abs/1303.3686

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