Equation of State and Composition of Proto-Neutron Stars and Merger Remnants with Hyperons

Finite-temperature equation of state (EoS) and the composition dense nuclear hypernuclear matter under conditions characteristic neutron star binary merger remnants supernovas are discussed. We consider both neutrino free-streaming trapped regimes which separated by a temperature few MeV. The formalism is based on covariant density functional (CDF) theory for full baryon octet with density-dependent couplings, suitably adjusted in sector. softening EoS introduction hyperons quantified various lepton fractions temperatures. find that $\Lambda$, $\Xi^-$, $\Xi^0$ appear given order sharp increase at zero threshold being replaced an extended increment over wide range high $\Lambda$ hyperon survives deep subnuclear regime. triplet $\Sigma$s suppressed cold up to around seven times saturation density, but appears significant higher temperatures, $T\geq 20$ MeV, supernova remnant matter. point out special isospin degeneracy exists where abundances within each three multiplets equal other as result (approximate) symmetry. At point, charge chemical potential system vanishes. conditions, electron $\mu$-on neutrinos close about 1\%, whereas case, we only fraction ($\sim$10\%) neutrinos, this number zero.