QCD thermodynamics and magnetization in nonzero magnetic field

TL;DR

This study investigates the magnetic and thermodynamic properties of QCD matter under nonzero magnetic fields using hadron resonance gas and Polyakov linear-sigma models, revealing paramagnetism and inverse magnetic catalysis effects.

Contribution

It compares two models' effectiveness in describing QCD matter in magnetic fields and highlights the models' ability to capture paramagnetic behavior and inverse magnetic catalysis phenomena.

Findings

QCD matter exhibits paramagnetic properties dependent on temperature.

Increasing magnetic field enhances thermodynamic quantities in the hadronic phase.

Magnetic field reduces the critical temperature, indicating inverse magnetic catalysis.

Abstract

In nonzero magnetic field, the magnetic properties and thermodynamics of the quantum-chromodynamic (QCD) matter is studied in the hadron resonance gas and the Polyakov linear-sigma models and compared with recent lattice calculations. Both models are fairly suited to describe the degrees of freedom in the hadronic phase. The partonic ones are only accessible by the second model. It is found that the QCD matter has paramagnetic properties, which monotonically depend on the temperature and are not affected by the hadron-quark phase-transition. Furthermore, raising the magnetic field strength increases the thermodynamic quantities, especially in the hadronic phase but reduces the critical temperature, i.e. inverse magnetic catalysis.