Influence of pions and hyperons on stellar black hole formation

TL;DR

This study uses numerical simulations to explore how the inclusion of pions and hyperons in the equation of state affects the timing and dynamics of black hole formation during stellar core-collapse.

Contribution

It introduces a new neutrino treatment scheme and demonstrates the impact of hyperonic particles on proto-neutron star stability and collapse timing.

Findings

Models with hyperons have smaller maximum proto-neutron star masses.

Hyperonic matter phase transition occurs at high accretion rates.

Black hole formation occurs earlier with extended equations of state.

Abstract

We present numerical simulations of stellar core-collapse with spherically symmetric, general relativistic hydrodynamics up to black hole formation. Using the CoCoNuT code, with a newly developed grey leakage scheme for the neutrino treatment, we investigate the effects of including pions and \Lambda-hyperons into the equation of state at high densities and temperatures on the black hole formation process. Results show non-negligible differences between the models with reference equation of state without any additional particles and models with the extended ones. For the latter, the maximum masses supported by the proto-neutron star are smaller and the collapse to a black hole occurs earlier. A phase transition to hyperonic matter is observed when the progenitor allows for a high enough accretion rate onto the proto-neutron star. Rough estimates of neutrino luminosity from these collapses are given, too.