On the connection between AGN radiative feedback and massive black hole spin

Active-galactic-nucleus (AGN) feedback has nowadays become an imperative ingredient in modern theories of galaxy formation to reproduce key observables of galaxy populations and it is routinely incorporated both in semi-analytic and hydrodynamical simulation models. In this doctoral thesis, I present a new model for AGN feedback in numerical simulations, which takes into account the spin-dependence of feedback anisotropy. Then, I explore some applications of it aimed at advancing our understanding of massive black holes (MBHs) growth, dynamics and their interaction with the host galaxy. In § 1.1, I begin the discussion by introducing relevant concepts about AGNs from both an observational and theoretical perspective. In § 1.2 I outline the fundamentals of AGN feedback, explaining the processes through which AGNs release energy and influence the evolution of their host galaxies. Section § 1.3 provides insights into the dynamic evolution of pairs and binaries of MBHs and shows how feedback is involved in these processes. In § 2 I discuss the development of novel numerical recipe for AGN feedback that accounts for the angular dependence of radiative feedback upon black hole spin. I then show tests of this model and an initial application in the context of co-evolution between an AGN and its host isolated disc galaxy. Chapter 3 explores the dynamical friction driven inspiral of MBH pairs at tens of pc scale in circum-nuclear-discs, specifically considering the influence of spin-dependent anisotropic feedback. In § 4 I study the implication of this phenomenon on the migration of bound pc-scale MBHs in circum-binary discs. The main results and limitations of this thesis are summarized in § 5, concluding with a discussion of potential future developments for this project.