Non-perturbative dynamics and charge fluctuations in effective chiral models

V Skokov,B Friman,K Redlich

doi:10.1016/j.physletb.2012.01.022

Abstract

We discuss the properties of fluctuations of the electric charge in the vicinity of the chiral crossover transition within effective chiral models at finite temperature and vanishing net baryon density. The calculation includes non-perturbative dynamics implemented within the functional renormalization group approach. We study the temperature dependence of the electric charge susceptibilities in the linear sigma model and explore the role of quantum statistics. Within the Polyakov loop extended quark–meson model, we study the influence of the coupling of quarks to mesons and to an effective gluon field on charge fluctuations. We find a clear signal for the chiral crossover transition in the fluctuations of the electric charge. Accordingly, we stress the role of higher-order cumulants as probes of criticality related to the restoration of chiral symmetry and deconfinement.

Highlights

The critical behavior of strongly interacting matter related with chiral dynamics should be common to all models which reproduce the underlying chiral symmetry of QCD and the pattern of spontaneous chiral symmetry breaking at finite temperature
In this work we explore the characteristic behavior of fluctuations of the electric charge near the chiral transition at vanishing chemical potential within the functional renormalization group (FRG) approach to the linear sigma and Polyakov-loop extended quark (PQM) models
The charge fluctuations reflect the critical behavior of the fluctuations of the net baryon density

Summary

Introduction

The critical behavior of strongly interacting matter related with chiral dynamics should be common to all models which reproduce the underlying chiral symmetry of QCD and the pattern of spontaneous chiral symmetry breaking at finite temperature. In this work we explore the characteristic behavior of fluctuations of the electric charge near the chiral transition at vanishing chemical potential within the functional renormalization group (FRG) approach to the linear sigma and Polyakov-loop extended quark (PQM) models.

Results

Conclusion