Cold magnetized quark matter at finite density in a nonlocal chiral quark model

TL;DR

This paper investigates how external magnetic fields influence dense quark matter using a nonlocal chiral quark model, revealing inverse magnetic catalysis at moderate fields and stable critical chemical potential at higher fields.

Contribution

It introduces a nonlocal chiral quark model with Gaussian form factors to study magnetic effects on dense quark matter, highlighting differences from local models.

Findings

Inverse magnetic catalysis at low to moderate magnetic fields.

Critical chemical potential becomes flat at high magnetic fields.

No significant increase in critical chemical potential for large magnetic fields.

Abstract

We study the behavior of two-flavor dense quark matter under the influence of an external magnetic field in the framework of a nonlocal chiral quark model with separable interactions. The nonlocality is incorporated in the model by using a Gaussian form factor. It is found that for low and moderate values of magnetic field there is a decrease of the critical chiral restoration chemical potential $\mu_c$, i.e. an inverse magnetic catalysis effect is observed. For larger values of $eB$ the behavior of $\mu_c$ becomes more or less flat, depending on the parametrization. Within the considered parametrization range we do not find a significant growth of the critical chemical potential for large magnetic fields, as occurs in the case of the local NJL model.