QGP flow fluctuations and the characteristics of higher moments

TL;DR

This paper investigates the development of Quark-gluon Plasma flow and higher moments in heavy-ion collisions using a 3+1D fluid dynamical model, highlighting deviations from thermal equilibrium due to expansion dynamics.

Contribution

It introduces a conservative fluid dynamical model with minimized fluctuations and supercooling, providing new insights into QGP flow fluctuations and higher moments at LHC energies.

Findings

Significant deviations from thermal equilibrium in QGP flow.

Impact of initial condition fluctuations on higher moments.

Insights into thermodynamical evolution at different energies.

Abstract

The dynamical development of expanding Quark-gluon Plasma (QGP) flow is studied in a 3+1D fluid dynamical model with a globally symmetric, initial condition. We minimize fluctuations arising from complex dynamical processes at finite impact parameters and from fluctuating random initial conditions to have a conservative fluid dynamical background estimate for the statistical distributions of the thermodynamical parameters. We also avoid a phase transition in the equation of state, and we let the matter supercool during the expansion. Then central Pb+Pb collisions at $\sqrt{s_{NN}} = 2.76$ TeV are studied in an almost perfect fluid dynamical model, with azimuthally symmetric initial state generated in a dynamical flux-tube model. The general development of thermodynamical extensives are also shown for lower energies. We observe considerable deviations from a thermal equilibrium source as a consequence of the fluid dynamical expansion arising from a least fluctuating initial state.