Time-evolution of fluctuations as signal of the phase transition dynamics in a QCD-assisted transport approach

TL;DR

This paper introduces a QCD-assisted transport model to study the time evolution of fluctuations near the QCD critical point, helping identify phase boundaries and critical regions in heavy-ion collision dynamics.

Contribution

It presents a novel non-equilibrium chiral fluid dynamics approach incorporating low energy QCD to analyze fluctuation evolution.

Findings

Estimated equilibration times of critical fluctuations.

Identified phase boundary and critical region near QCD critical point.

Analyzed kurtosis evolution in a non-expanding system.

Abstract

For the understanding of fluctuation measurements in heavy-ion collisions it is crucial to develop quantitatively reliable dynamical descriptions which take the non-perturbative nature of QCD near the phase transition into account. We discuss a novel QCD-assisted transport approach based on non-equilibrium chiral fluid dynamics and the effective action of low energy QCD. In this framework, we study the time-evolution of fluctuation measures of the critical mode, notably the kurtosis, for a non-expanding system. From this, we can estimate the equilibration times of critical mode fluctuations in the QCD phase diagram. These allow us to identify both the phase boundary and the critical region near the QCD critical point.