The QCD phase transition in a fully dynamical model of heavy-ion collisions

Abstract

Experimental signals for a possible QCD critical point and first-order phase transition are strongly influenced by the rapid nonequilibrium dynamics during a heavy-ion collision. In order to estimate and understand these effects we study the cooling through the phase transition within a nonequilibrium chiral fluid dynamics model. The order parameters for the chiral and deconfinement transition are explicitly propagated, taking into account dissipation and fluctuation stemming from the interaction with a quark-antiquark fluid. In studies of single events, we demonstrate how the formation of domains in net-baryon density at the first-order phase transition leads to a clear enhancement of higher flow harmonics. For the detection of the critical point it is crucial that the relevant signal survives the rapid dynamics. We observe critical slowing down and long-wavelength fluctuations in the vicinity of the critical point.