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In this work, we delve into the temperature-dependent Equation of State (EoS) of baryonic matter within the framework of the FSU2H* hadronic model, which comprehensively incorporates hyperons and is suitable for relativistic simulations of neutron star mergers and supernovae. To assess the impact of the uncertainties in the hyperonic sector on astrophysical observables, we introduce two additional models, namely FSU2H*L (FSU2H*-Lower) and FSU2H*U(FSU2H*-Upper). These models cover the entire spectrum of variability of hyperonic potentials, as derived from experimental data. Our investigations reveal that these uncertainties extend their influence not only to the relative abundances of various particle species but also to the EoS itself and, consequently, have an impact on the global properties of both cold and hot neutron stars. Notably, their effects become more pronounced at large temperatures, owing to the increased presence of hyperons. These findings have direct implications for the outcomes of relativistic simulations of neutron star mergers and supernovae, emphasizing the need of accounting for hyperonic uncertainties to ensure the accuracy and reliability of such simulations in astrophysical contexts. [ABSTRACT FROM AUTHOR]

The FSU2H equation-of-state model, originally developed to describe cold neutron star matter with hyperonic cores, is extended to finite temperature. Results are presented for a wide range of temperatures and lepton fractions, which cover the conditions met in protoneutron star matter, neutron star mergers, and supernova explosions. It is found that the temperature effects on the thermodynamical observables and the composition of the neutron star core are stronger when the hyperonic degrees of freedom are considered. An evaluation of the temperature and density dependence of the thermal index leads to the observation that the so-called Γ law, widely used in neutron star merger simulations, is not appropriate to reproduce the true thermal effects, specially when hyperons start to be abundant in the neutron star core. To make finite temperature equations of state easily accessible, simple parametrizations of the thermal index for nucleonic and hyperonic β-stable neutrino-free matter are provided. [ABSTRACT FROM AUTHOR]

An analytic parametrization of the cold hypernuclear matter equation of state based on microscopic Brueckner–Hartree–Fock calculations is constructed using realistic nucleon-nucleon and hyperon-nucleon interactions. The parametrization is based on a simple phase-space analysis and reproduces with good accuracy the results of the microscopic calculations with a small number of parameters. This parametrization allows for rapid calculations that accurately mimic the microscopic results, being therefore very useful from a practical point of view. As an example, we determine the composition and some properties of neutron stars, such as mass-radius relation, tidal deformability and moment of inertia, using the equation of state derived from this parametrization. [ABSTRACT FROM AUTHOR]