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arXiv · 1210.7435

Influence of pions and hyperons on stellar black hole formation

Bruno Peres·Micaela Oertel·Jerome Novak
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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 Λ-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.

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Bruno Peres, Micaela Oertel, Jerome Novak. 2013-01-10. Influence of pions and hyperons on stellar black hole formation. https://doi.org/10.1103/physrevd.87.043006

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