SPEAKER: Prof. Francesco Shankar (University of Southampton, UK)
TITLE: A new benchmark for the local and high-z scaling relations of supermassive black holes: Dissecting the roles of AGN feedback and black hole mergers
ABSTRACT: The correlations between Supermassive Black Hole (SMBH) mass and host galaxy properties can reveal the processes shaping the coevolution of SMBHs and galaxies, from mergers to Active Galactic Nuclei (AGN) feedback. However, a clear knowledge of the exact shape and evolution of these relations is still missing. In this talk, I will present the latest results on the SMBH scaling relations, their residuals, and their time evolution. I will first show that stellar velocity dispersion is, according to the latest available data from local dynamical inactive SMBHs, the key galactic property linked to SMBH mass in the local Universe. The correlation with other galactic properties at fixed stellar velocity dispersion are significantly less strong or disappear entirely, implying that interpreting the co-evolution between SMBHs and their host galaxies uniquely on the Mbh-Mgal plane may lead to inaccurate conclusions. Interestingly, I will also show very new results on the (allegedly strong) correlation between SMBH mass and host halo mass. I will discuss all these empirical trends and compare them with the outputs of state-of-the-art hydrodynamic simulations and semi-analytic models. I will then move to the higher redshift Universe, and demonstrate how current high-z data in terms of (integrated) X-ray luminosities and star formation histories, all suggest a weak evolution of the SMBH-galaxy scaling relations up to at least z∼2-3, providing a robust benchmark for coevolution models. I will conclude by presenting a cutting-edge comprehensive semi-empirical/data-driven model for the evolution of SMBHs in a cosmological context, inclusive of mergers and accretion rates in line with observed Eddington ratio distribution, starting from the high-z conditions imposed by luminous red dots to the local Universe.
Poster of the event is available at:
https://rebrand.ly/JAC-Shankar-Poster
