The growth of supermassive black holes is dominated by galaxy merger-free processes

Add to your list(s) Download to your calendar using vCal

• Rebecca Smethurst University of Oxford
• Thursday 14 November 2024, 16:00-17:00
• Hoyle Lecture Theatre, Institute of Astronomy.

If you have a question about this talk, please contact Jan Scholtz.

The strong correlations that are found between supermassive black hole (SMBH) mass and velocity dispersion, stellar mass and bulge mass have long been interpreted as co-evolution of galaxies and their SMB Hs through galaxy mergers. However, a flurry of new results, both observational and theoretical, have suggested that galaxy mergers may not be the dominant mechanism powering this co-evolution. I shall review these findings before presenting results showing that merger-free galaxies have SMB Hs up to a billion solar masses and have substantial energetic outflows powered by the active galactic nuclei (AGN). In addition I will present work in collaboration with the Horizon-AGN simulation team showing that merger-free evolutionary processes also lead to co-evolution of galaxies and their SMB Hs. This has interesting implications: if both galaxy-merger-driven and galaxy-merger-free SMBH growth leads to co-evolution, this suggests that co-evolution is regulated by AGN feedback in both scenarios. AGN feedback is thought to be a key regulator of co-evolution and considered necessary in cosmological volume simulations employing ΛCDM, yet the role of AGN feedback in the absence of mergers is currently unknown. I will therefore discuss the future observations needed to understand the role of this understudied merger-free co-evolution pathway.

This talk is part of the Institute of Astronomy Colloquia series.

This talk is included in these lists:

• Cambridge Astronomy Talks
• Combined External Astrophysics Talks DAMTP
• Cosmology lists
• Cosmology, Astrophysics and General Relativity
• Hoyle Lecture Theatre, Institute of Astronomy
• Institute of Astronomy Colloquia
• Institute of Astronomy Talk Lists
• Kavli Institute for Cosmology Talk Lists
• Priscilla

Note that ex-directory lists are not shown.