Proto-neutron stars with heavy baryons and universal relations

Abstract

We use covariant density functional theory to obtain the equation of state (EoS) of matter in compact stars at non-zero temperature, including the full baryon octet as well as the $\Delta (1232)$ resonance states. Global properties of hot $\Delta$-admixed hypernuclear stars are computed for fixed values of entropy per baryon ($S/A$) and lepton fraction ($Y_L$). Universal relations between the moment of inertia, quadrupole moment, tidal deformability, and compactness of compact stars are established for fixed values of $S/A$ and $Y_L$ that are analogous to those known for cold catalyzed compact stars. We also verify that the $I$-Love-$Q$ relations hold at finite temperature for constant values of $S/A$ and $Y_L$.

Comments: 20 pages, 15 figures