Spectrum of the Supernova Relic Neutrino Background and Metallicity Evolution of Galaxies

Understand

The spectrum of the supernova relic neutrino (SRN) background from past stellar collapses including black hole formation (failed supernovae) is calculated.

• The redshift dependence of the black hole formation rate is considered on the basis of the metallicity evolution of galaxies.
• Assuming the mass and metallicity ranges of failed supernova progenitors, their contribution to SRNs is quantitatively estimated for the first time.
• Using this model, the dependences of SRNs on the cosmic star formation rate density, shock revival time and equation of state are investigated.