Non-perturbative dynamics and charge fluctuations in effective chiral models

TL;DR

This paper investigates electric charge fluctuations near the chiral crossover transition using effective chiral models with non-perturbative dynamics, highlighting the role of higher order cumulants as criticality probes.

Contribution

It introduces a non-perturbative approach to study charge fluctuations in chiral models, emphasizing the impact of quantum statistics and quark-gluon coupling on critical phenomena.

Findings

Charge fluctuations signal the chiral crossover transition.

Higher order cumulants serve as probes of criticality.

Quantum statistics influence charge susceptibility behavior.

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.