Related papers: Models of AGN feedback
We show how the interplay between active galactic nuclei (AGN) and merger history determines whether a galaxy quenches star formation at high redshift. We first simulate, in a full cosmological context, a galaxy of total dynamical mass…
The current paradigm for radio-quiet AGNs is reviewed, taking into account new results from recent large-scale surveys carried out from the ground and from space. Topics include structure of the central engine, AGN demography,…
We review the results from multi-dimensional, time-dependent simulations of gas dynamics in AGN. We will focus on two types of outflows powered by radiation emitted from the AGN central engine: (i) outflows driven from the innermost part of…
The study of the conditions and the kinematics of the gas in the central region of AGN provides important information on the relevance of feedback effects connected to the nuclear activity. Quantifying these effects is key for constraining…
Radiative cooling may plausibly cause hot gas in the centre of a massive galaxy, or galaxy cluster, to become gravitationally unstable. The subsequent collapse of this gas on a dynamical timescale can provide an abundant source of fuel for…
The discovery of the M-sigma relation, the local galaxy bimodality, and the link between black-hole and host-galaxy properties, have raised the question whether AGN play a role in galaxy evolution. Several theoretical models implement AGN…
We investigate the effects of AGN feedback on the cosmological evolution of an isolated elliptical galaxy by performing two-dimensional high-resolution hydrodynamical numerical simulations. The inner boundary of the simulation is chosen so…
Observations at multiple wavelengths are reviewed to search for evidence for fueling mechanisms in galaxies, both for nuclear starbursts and AGN activity. Although it is undisputed that dynamical perturbations such as bars or tidal…
We post-process galaxy star formation histories in cosmological hydrodynamics simulations to test quenching mechanisms associated with AGN. By comparing simulation results to color-magnitude diagrams and luminosity functions of SDSS…
Galaxy evolution is affected by competing feedback processes. Stellar feedback dominates in low-mass galaxies, while AGN feedback predominantly affects massive ones. Recent observational results reveal the dependence of black hole accretion…
I show that Eddington accretion episodes in AGN are likely to produce winds with velocities $v \sim 0.1c$ and ionization parameters up to $\xi \sim 10^4$ (cgs), implying the presence of resonance lines of helium-- and hydrogenlike iron.…
Active galactic nuclei (AGN) are among the most energetic phenomena in the universe, capable of regulating star formation in galaxies via radiative and mechanical feedback. While AGN feedback is well studied in host galaxies, its influence…
We describe a physical model of the outflows produced as a result of gas accretion onto a black hole, and the resultant changes to star formation rates and efficiencies in galaxies, using the Radio-SAGE semi-analytic galaxy formation model.…
Different mechanisms can drive outflows in active galactic nuclei (AGN), but it is often unclear which mechanism dominates, if any. To quantify the impact of AGN feedback on galaxy evolution, the driving mechanism of outflows must be better…
We present some results of the new MORGANA model for the rise of galaxies and active nuclei, and show that the improved physical motivation of the description of star formation and feedback allows to get hints on the physical processes at…
Massive gas outflows are considered a key component in the process of galaxy formation and evolution. It is, therefore, not surprising that a lot of effort is going in quantifying their impact via detailed observations. This short…
A long-standing problem for models of galaxy formation has been the mismatch between the predicted shape of the mass function of dark matter halos and the observed shape of the luminosity function of galaxies. The number of massive halos is…
To accommodate the seemingly "anti-hierarchical" properties of galaxies near the upper end of the mass function within our hierarchical paradigm, current models of galaxy evolution postulate a phase of vigorous AGN feedback at high…
Galaxies often contain large reservoirs of molecular gas which shape their evolution. This can be through cooling of the gas -- which leads to star formation, or accretion onto the central supermassive black hole -- which fuels AGN activity…
The tight empirical $M-\sigma$ relation between the mass of a SMBH) and the velocity dispersion of the host galaxy bulge is often interpreted as the result of self-regulation by AGN feedback. This picture is motivated by analytical and…