Structural properties of charged compact stars with color-flavour-locked quarks matter

TL;DR

This paper explores how electric charge influences the structure and observable properties of quark stars in the color-flavor-locked phase, aiming to explain massive pulsars within theoretical models.

Contribution

It introduces a model incorporating electric charge proportional to mass density in CFL quark stars and analyzes their structural properties and stability, extending previous work on uncharged models.

Findings

Charged CFL quark stars can reach masses close to 2 solar masses.

Electric charge affects the mass-radius relation and stability of quark stars.

Results are consistent with recent observational data on pulsar masses and radii.

Abstract

The observations of pulsars with masses close to 2$M_{\odot}$ have put strong constraints on the equation of state (EoS) of neutron-rich matter at supranuclear densities. Moreover, the exact internal composition of those objects is largely unknown to us. Aiming to reach the 2$M_{\odot}$ limit, here we investigate the impact of electric charge on properties of compact stars assuming that the charge distribution is proportional to the mass density. The study is carried out by solving the Tolman-Oppenheimer-Volkoff (TOV) equation for a well-motivated exotic quark matter in the color-flavor-locked (CFL) phase of color superconductivity. The existence of the CFL phase may be the true ground state of hadronic matter with the possibility of the existence of a pure stable quark star (QS). Concerning the equation-of-state, we obtain structural properties of quark stars and compute the mass, the radius as well as the total electric charge of the star. We analyze the dependence of the physical properties of these QSs depending on the free parameters with special attention on mass-radius relation. We also briefly discuss the mass vs central mass density $(M-\epsilon_c)$ relation for stability, the effect of electric charge and compactness. Finally, our results are compared with the recent observations data on mass-radius relationship.