The low-end of the black hole mass function at cosmic dawn

Understand

Understanding the formation and growth of supermassive black holes (SMBHs) at high redshift represents a major challenge for theoretical models.

• In this work we investigate the early evolution of the first SMBHs by constraining their distribution in mass and luminosity at $z > 4$.
• In particular, we focus on the poorly explored low-mass end of the nuclear black hole (BH) distribution down to $z \simeq 4$, and explore its connection with the nature of the first BH seeds and the processes governing their mass growth.
• To this aim, we have developed CAT (Cosmic Archaeology Tool), a new semi-analytic model that describes the formation of the first stars and black holes in a self-consistent way and follows the co-evolution of nuclear BHs and their host galaxies for a representative population at $z > 4$.