Dynamics of the conserved net-baryon density near QCD critical point within inhomogeneous quark-gluon plasma profile

TL;DR

This study explores how inhomogeneous temperature and chemical potential profiles in quark-gluon plasma influence net-baryon fluctuations near the QCD critical point, revealing enhanced fluctuations due to inhomogeneity and critical slowing down.

Contribution

It introduces a numerical approach to study the Langevin dynamics of conserved net-baryon density within inhomogeneous profiles from hydrodynamic simulations, highlighting the impact on fluctuation enhancement.

Findings

Different rapidities reach the critical point at different times.

Enhanced net-baryon fluctuations observed at freeze-out surface.

Inhomogeneity and critical slowing down jointly amplify fluctuations.

Abstract

This paper investigates the dynamics of the net-baryon multiplicity fluctuations near the QCD critical point, within the inhomogeneous temperature and baryon chemical potential profile of quark-gluon plasma from the hydrodynamics. The Langevin dynamics of conserved net-baryon density are solved numerically within the temperature and chemical potential profile borrowing from hydrodynamic simulation. It is found that the local systems at different rapidities reach the critical point at different proper times, owing to the inhomogeneous temperature and chemical potential. As a result, it is observed the pronounced enhancement of the magnitude for the net-baryon multiplicity fluctuations with large rapidity acceptance at the freeze-out surface, which is the consequence of the combined effect of critical slowing down and inhomogeneous profile.