Charged ρ-meson condensation in neutron stars

We extend relativistic mean-field models with hadron masses and meson-baryon coupling constants dependent on the scalar field σ, including hyperons and Δ(1232) baryons, to incorporate a possibility of the charged ρ meson condensation in neutron star matter. The influence of the ρ− condensation on the equation of state proves to be strongly model dependent. In our models of one type (KVORcut-based ones) the ρ− condensation arises by a second-order phase transition above a critical density and the maximum value of the neutron star mass diminishes only slightly. The matter composition changes more significantly. In our models of other type (MKVOR*-based ones), if the system is considered at fixed density, the ρ− condensation arises by a second-order phase transition at the baryon density n=nc,ρ(II) and at a slightly higher density n=nc,ρ(I) there occurs a first-order phase transition. In a neutron star matter starting with a density n