Small quark stars in the chromodielectric model

Abstract

Equations of state for strange quark matter in beta equilibrium at high densities are used to investigate the structure (mass and radius) of compact objects. The chromodielectric model is used as a general framework for the quark interactions, which are mediated by chiral mesons, $σ$ and $\vec π$, and by a confining chiral singlet dynamical field, $χ$. Using a quartic potential for $χ$, two equations of state for the same set of model parameters are obtained, one with a minimum at around the nuclear matter density $ρ_0$ and the other at $ρ\sim 5 ρ_0$. Using the latter equation of state in the Tolman-Oppenheimer-Volkoff equations we found solutions corresponding to compact objects with $R\sim 5 - 8$ km and $M\sim M_\odot$. The phenomenology of recently discovered X-ray sources is compatible with the type of quark stars that we have obtained.