The many facets of black hole feedback in galaxies

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Our understanding of the Universe has progressed tremendously over the past decades. Yet, we still do not understand how galaxies - the building blocks of the Universe - form and evolve with cosmic time. What has become clear from cosmological simulations, as well as mounting evidence from observations, is that supermassive black holes play a fundamental and essential role in regulating the formation of stars throughout cosmic time. This has been clearly demonstrated in the case of galaxy clusters, in which powerful feedback from the central supermassive black hole is preventing the hot intracluster gas from cooling catastrophically; reducing the expected star formation rates by orders of magnitude. However, exactly how black holes release their energy or how this energy interacts with its surrounding, ultimately shaping the properties galaxies, is still not well understood. The long-term goal of this program is to determine in detail how supermassive black holes shape the properties of galaxies with a particular focus on understanding the impact of black hole jets on their surroundings; this is a key stepping-stone for our understanding of how galaxies form and evolve with cosmic time. I intend to play a pivotal role in this field by tackling the problem via well-tested methods and well-established collaborations that I have developed over my career. The current proposal focusses on four short-term objectives that are based on a series of novel observations from space-based telescopes such as the Hubble Space Telescope and the Chandra X-ray Observatory, as well as ground-based observatories such as the recently upgraded Very Large Array and the Canada-France-Hawaii telescope. Most of these observations have already been allocated to me as principal investigator. More specifically, to understand the various ways in which black hole jets interact with their surroundings, this proposal will address the following items: from understanding the impact of black holes jets on the gas within the spheres of influence of the black holes (e.g. via Hubble/STIS observations), to understanding the role of positive and negative feedback from black hole jets on the scale of their galaxies (e.g. via observations of the multiphase gas surrounding black hole jets), as well as the impact of black hole jets on scales larger than their galaxy (e.g. via observations of large-scale diffuse radio synchrotron emission) and throughout time. Most of this science will target the black holes at the centers of galaxy clusters because these objects provide an environment in which we can directly witness the impact of black hole jets on the environment surrounding galaxies via observations of the hot intracluster medium visible at X-ray wavelengths. Overall, this proposal promises to enable cutting-edge discoveries within my team, in Canada, as well as at the international level.