Proto-neutron stars with heavy baryons and universal relations

TL;DR

This paper investigates the properties of hot, baryon-rich neutron stars including heavy baryons and resonances, establishing universal relations among their global parameters at finite temperature.

Contribution

It extends the universal I-Love-Q relations to hot neutron stars with heavy baryons and resonances using covariant density functional theory.

Findings

Universal relations hold at finite temperature for fixed entropy and lepton fraction.

The equation of state includes full baryon octet and $ riangle(1232)$ resonances.

Global properties of hot hypernuclear stars are characterized.

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 $Y_L$.