Domain of parameters in a model with density-dependent quark mass

Abstract

The strange quark matter in the CFL (Color-Flavor-Locked) superconducting phase at zero temperature has been taken as the ground state of Quantum Chromodynamics (QCD) for light flavors (u, d, s) [1]. In this work, the CFL matter is being studied in a phenomenological approach where the interaction between quarks is taken into account by incorporating a density dependence of the in-medium quark mass in the calculation. The pairing effect is considered in the thermodynamical potential of the system, taking the CFL superconducting gap as a free parameter. The stability of the superconducting quark matter is discussed analyzing the equation of state of the system for different values of the parameters used for the description of the employed phenomenological model. The main purpose here is to study the limit values of these parameters to maintain the CFL phase as the lowest energy state of the quark matter.