Traces of non-equilibrium dynamics in relativistic heavy-ion collisions

Abstract

The impact of non-equilibrium effects on the dynamics of heavy-ion collisions is investigated by comparing a non-equilibrium transport approach, the Parton-Hadron-String-Dynamics (PHSD), to a 2D+1 viscous hydrodynamical model, which is based on the assumption of local equilibrium and conservation laws. Starting the hydrodynamical model from the same non-equilibrium initial condition as in the PHSD, using an equivalent lQCD Equation-of-State (EoS), the same transport coefficients, i.e. shear viscosity $\eta$ and the bulk viscosity $\zeta$ in the hydrodynamical model, we compare the time evolution of the system in terms of energy density, Fourier transformed energy density, spatial and momentum eccentricities and ellipticity in order to quantify the traces of non-equilibrium phenomena. In addition, we also investigate the role of initial pre-equilibrium flow on the hydrodynamical evolution and demonstrate its importance for final state observables. We find that due to non-equilibrium effects, the event-by-event transport calculations show large fluctuations in the collective properties, while ensemble averaged observables are close to the hydrodynamical results.

19 pages, 16 figures

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Cited by in corpus (11)

• Extraction of Heavy-Flavor Transport Coefficients in QCD Matter
• Exploring the partonic phase at finite chemical potential within an extended off-shell transport approach
• Cracking the difference of estimating heavy quark transport coefficients in a Quark-Gluon Plasma
• Transport coefficients for the hot quark-gluon plasma at finite chemical potential ${\mu }_B$
• Exploring non-equilibrium quark-gluon plasma effects on charm transport coefficients
• Traces of non-equilibrium effects, initial condition, bulk dynamics and elementary collisions in the charm observables
• Two-particle correlations at high-energy nuclear collisions, peripheral-tube model revisited
• On the peripheral-tube description of the two-particle correlations in nuclear collisions
• Temperature fluctuations and Tsallis statistics in Relativistic Heavy Ion collisions
• Kinetic evolution and correlation of fluctuations in an expanding quark gluon plasma
• Hubble's Law in Heavy Ion Collisions