Heavy-quark effects on cold quark matter and self-bound stars

Heavy-quark effects on the equation of state for cold and dense quark matter are obtained from perturbative QCD, yielding observables parametrized only by renormalization scale. In particular, we investigate thermodynamics charm under constraints $\beta$ equilibrium electric charge neutrality in a region densities where QCD is, principle, much more reliable. Finally, analyze stability stars, possible new branch ultradense, self-bound compact find that they unstable radial oscillations.