Neutron stars with a dark-energy core from the Chaplygin gas

Abstract

We analyze the effect of a Chaplygin dark fluid (CDF) core on neutron stars (NSs). To address this study, we focus on the relativistic structure of stellar configurations composed by a dark-energy core, described by a Chaplygin-like equation of state (EoS), and an ordinary-matter crust which is described by a polytropic EoS. We examine the impact of the rate of energy densities at the discontinuous surface, defined as $\alpha= \rho_{\rm dis}^-/\rho_{\rm dis}^+$, on the radius, total gravitational mass, oscillation spectrum and tidal deformability. Furthermore, we compare our theoretical predictions with several observational mass-radius measurements and tidal deformability constraints. These comparisons together with the radial stability analysis show that the existence of NSs with a dark-energy core is possible.