Anisotropic pressure of magnetized quark matter with anomalous magnetic moment

TL;DR

This paper studies how strong magnetic fields affect the properties of quark matter, including pressure, magnetization, and phase transitions, using a modified NJL model with anomalous magnetic moments at finite temperature and density.

Contribution

It introduces the effects of anomalous magnetic moments on magnetized quark matter within the Polyakov NJL model, highlighting their impact on phase transition and magnetic properties.

Findings

Transverse pressure and magnetization oscillate at high magnetic fields in the broken phase.

Oscillations diminish at higher temperature and chemical potential, indicating partial chiral symmetry restoration.

Magnetic susceptibility remains positive above the transition, showing paramagnetic behavior.

Abstract

We investigate magnetic field $(eB)$ dependence of constituent quark mass, the longitudinal and transverse pressure as well as the magnetization and magnetic susceptibility of strongly interacting quark matter. We employ the two-flavour Polyakov Nambu--Jona-Lasinio model with the inclusion of the anomalous magnetic moment (AMM) of the quarks at finite temperature $(T)$ and finite quark chemical potential $(\mu_q)$ capturing different stages of chiral phase transition. We find that the transverse pressure, magnetization and magnetic susceptibility become highly oscillatory for large values of $eB$ in the chiral symmetry broken phase. However the oscillations cease to occur at higher values of $T$ and $\mu_q$ when chiral symmetry is (partially) restored and the anisotropic nature of the pressure becomes significant even at smaller values of $eB$. As the inclusion of AMM of the quarks leads to inverse magnetic catalysis of the transition temperature we observe that the variations of transverse pressure, magnetization and magnetic susceptibility are significantly modified in the vicinity of the chiral transition temperature. Furthermore, above the chiral transition temperature the magnetic susceptibility is found to remain positive for a wide range of $eB$ indicating a paramagnetic character of the strongly interacting quark matter. Finally, we have also examined the magnetism of strongly interacting matter in the quarkyonic phase. The obtained results could be useful for a magnetohydrodynamic evolution of hot and dense matter created in heavy-ion collisions.