QCD chiral condensate and pseudoscalar-meson properties in the nuclear medium at finite temperature

TL;DR

This study investigates how the properties of pions, kaons, and the QCD chiral condensate change in nuclear matter at finite temperature and magnetic fields using the NJL model with proper-time regularization, revealing density, temperature, and magnetic field effects.

Contribution

It introduces a combined NJL and QMC model approach to analyze meson properties and chiral condensates in nuclear medium at finite temperature and magnetic field, incorporating confinement effects.

Findings

Chiral condensates decrease with temperature and density, increase with magnetic field.

Wave function renormalization factors for pions and kaons vary with temperature and density.

Meson masses and decay constants are affected by medium conditions, consistent with other models.

Abstract

The pion and kaon properties in a nuclear medium at nonvanishing temperature as well as the QCD chiral condensate in the presence of a magnetic field for various baryon densities are studied in the Nambu-Jona-Lasinio (NJL) model with the help of the proper-time regularization (PTR) scheme, simulating a QCD confinement. The density dependent of the quark mass in symmetric nuclear matter is obtained from the quark-meson coupling (QMC) model, which shares the same covariant feature with the NJL model, at quark level. We then analyze the QCD chiral condensates, and dynamical masses for various baryon densities at finite temperature and magnetic field as well as the pion and kaon masses, pion and kaon weak-decay constants, pion-and kaon-quark coupling constants, and wave function renormalization factors for various baryon densities at finite temperature. We find that the QCD chiral condensates suppress with increasing temperature and baryon density and enhance under the presence of a magnetic field, which are consistent with other model predictions. Interestingly, the wave function renormalization factors for the pion and kaon increase with respect to temperature and reduce as the baryon density increases are found.