Quark-meson coupling model for antikaon condensation in neutron star matter with strong magnetic fields

TL;DR

This paper investigates how strong magnetic fields influence antikaon condensation in neutron star matter using the quark-meson coupling model, revealing significant shifts in condensation thresholds and changes in the equation of state.

Contribution

It introduces the application of the QMC model to study magnetic field effects on antikaon condensation, highlighting differences from RMF model predictions.

Findings

Strong magnetic fields significantly alter the threshold density for antikaon condensation.

Magnetic fields cause the equation of state to become stiffer compared to the field-free case.

The softening effect of antikaon condensation on the EOS diminishes with increasing magnetic field strength.

Abstract

We study the effects of strong magnetic fields on antikaon condensation in neutron star matter using the quark-meson coupling (QMC) model. The QMC model describes a nuclear many-body system as nonoverlapping MIT bags in which quarks interact through the self-consistent exchange of scalar and vector mesons in the mean-field approximation. It is found that the presence of strong magnetic fields alters the threshold density of antikaon condensation significantly. The onset of $K^-$ condensation stronger depends on the magnetic field strength, and it even shifts beyond the threshold of $\bar K^0$ condensation for sufficiently strong magnetic fields. In the presence of strong magnetic fields, the equation of state (EOS) becomes stiffer in comparison with the field-free case. The softening of the EOS by antikaon condensation also depends on the magnetic field strength, and it becomes less pronounced with increasing magnetic field strength. The results of the QMC model are compared with those obtained in a relativistic mean-field (RMF) model, and we find there are quantitative differences between the results of the QMC and RMF models.