Speaker
Description
Stellar-mass black holes (BHs) are formed in the collapse of massive stars. The detailed pathways to BH formation are, however, still under active debate. In my talk, I will present results from a set of three-dimensional (3D) neutrino-hydrodynamics simulations of BH formation in failed core-collapse supernova explosions (sometimes called "unnovae"). Because failed supernovae lack a bright electromagnetic signal, neutrinos and gravitational waves are the only messengers that carry valuable information on the physical processes in the deep interiors of the collapsing stellar cores. In my presentation, I will discuss how the (highly turbulent) hydrodynamics of the stellar plasma shapes the anisotropic emission (and absorption/scattering) of neutrinos, which has important implications for the natal kicks of the remnant BHs. Moreover, I will demonstrate that neutrinos from failed supernovae contribute significantly to (or may even dominate) the diffuse supernova neutrino background (DSNB), which is the cumulative neutrino flux from past stellar core-collapse events at cosmological distances. The almost guaranteed discovery of the DSNB with currently running and next-generation neutrino experiments (such as Super-Kamiokande, JUNO, and Hyper-Kamiokande) will mark the next milestone in neutrino astronomy after SN 1987A and will allow to directly probe the theory of stellar BH formation.