Chiral medium produced by parallel electric and magnetic fields

TL;DR

This paper investigates how parallel electric and magnetic fields create a chiral medium in quark matter, lowering the critical temperature for chiral symmetry restoration by analyzing the medium's properties and relaxation dynamics.

Contribution

It introduces a model for the chiral medium produced by parallel fields and quantifies how these fields influence the chiral transition temperature in quark matter.

Findings

Chiral medium forms on a timescale of 0.1-1 fm/c.

External fields lower the critical temperature for chiral symmetry restoration.

Chiral density equilibrates due to microscopic processes in the thermal bath.

Abstract

We compute (pseudo)critical temperature, $T_c$, of chiral symmetry restoration for quark matter in the background of parallel electric and magnetic fields. This field configuration leads to the production of a chiral medium on a time scale $\tau$, characterized by a nonvanishing value of the chiral density that equilibrates due to microscopic processes in the thermal bath. We estimate the relaxation time $\tau$ to be about $\approx 0.1-1$ fm/c around the chiral crossover; then we compute the effect of the fields and of the chiral medium on~$T_c$. We find $T_c$ to be lowered by the external fields in the chiral medium.