Equation of state for the MCFL phase and its implications for compact star models

TL;DR

This paper derives the equation of state for the MCFL phase of quark matter under magnetic fields, exploring its stability and implications for modeling magnetized strange stars and hybrid stars.

Contribution

It provides a self-consistent calculation of the MCFL phase's equation of state considering magnetic effects and introduces a field-dependent bag constant for stability analysis.

Findings

Stable MCFL matter requires a magnetic field-dependent bag constant.

Existence of a stability window in magnetic field vs. bag constant plane.

Implications for the structure of magnetized strange and hybrid stars.

Abstract

Using the solutions of the gap equations of the magnetic-color-flavor-locked (MCFL) phase of paired quark matter in a magnetic field, and taking into consideration the separation between the longitudinal and transverse pressures due to the field-induced breaking of the spatial rotational symmetry, the equation of state (EoS) of the MCFL phase is self-consistently determined. This result is then used to investigate the possibility of absolute stability, which turns out to require a field-dependent bag constant to hold. That is, only if the bag constant varies with the magnetic field, there exists a window in the magnetic field vs. bag constant plane for absolute stability of strange matter. Implications for stellar models of magnetized (self-bound) strange stars and hybrid (MCFL core) stars are calculated and discussed.