Related papers: Why does Low-Luminosity AGN Fueling Remain an Unso…
We study the incidence of nuclear obscuration on a complete sample of 1310 AGN selected on the basis of their rest-frame 2-10 keV X-ray flux from the XMM-COSMOS survey, in the redshift range 0.3<z<3.5. We classify the AGN as obscured or…
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,…
The physical processes responsible of sweeping up the surrounding gas in the host galaxy of an AGN, and able in some circumstances to expel it from the galaxy, are not yet well known. The various mechanisms are briefly reviewed: quasar or…
There is strong observational evidence indicating a time lag of order of some 100 Myr between the onset of starburst and AGN activity in galaxies. Dynamical time lags have been invoked to explain this. We extend this approach by introducing…
Black hole mass, along with mass accretion rate, is a fundamental property of active galactic nuclei. Black hole mass sets an approximate upper limit to AGN energetics via the Eddington limit. We collect and compare all AGN black hole mass…
Recent observations have indicated that a large fraction of the low to intermediate luminosity AGN population lives in disk-dominated hosts, while the more luminous quasars live in bulge-dominated hosts, in conflict with some previous model…
Current mm-interferometers can provide a complete view of the distribution and kinematics of molecular gas in the circumnuclear disks of nearby galaxies. High-resolution CO maps are paramount in order to track down the feeding of active…
The depth and coverage of the first years of JWST observations have revealed low luminosity active galactic nuclei (AGN) across a wide redshift range, shedding light on black hole (BH) assembly and feedback. We present our spectroscopic…
In this paper we give a brief review of the astrophysics of active galactic nuclei (AGN). After a general introduction motivating the study of AGNs, we discuss our present understanding of the inner workings of the central engines, most…
The luminous electromagnetic emission from distant active galactic nuclei (AGNs) including quasars is believed to be powered by accretion onto super-massive black holes (SMBHs). In the standard unification model for AGNs a dusty torus…
AGN jets are thought to be vital ingredients in galaxy evolution through the action of kinetic feedback; however, how narrow, relativistic outflows couple to galaxies remains an open question. Jet deceleration, which is often attributed to…
AIMS: We investigate here the nature of all the sources (35 in total) in the XBS survey (which is 86% optically identified) showing an optical spectrum dominated by the light from the host galaxy with no evidence (or little evidence) for…
The cores of active galactic nuclei (AGN) harbor some of the most extreme conditions of matter and energy in the Universe. One of the major goals of high-energy astrophysics is to probe these extreme environments in the vicinity of…
Energetic gas outflows driven by active galactic nuclei (AGNs) are considered as one of the mechanisms, by which supermassive black holes affect their host galaxies. To probe the impact of AGN-driven outflows, it is essential to quantify…
Molecular gas is the key probe for the complex interaction between the accretion of black holes and star formation of the host galaxy of active galactic nuclei (AGN). The molecular gas discovered around the AGN indicates that this gas is…
The increasing observational evidence of galactic outflows is considered as a sign of active galactic nucleus (AGN) feedback in action. However, the physical mechanism responsible for driving the observed outflows remains unclear, and…
Relativistic jets are one of the most powerful manifestations of the release of energy related to the supermassive black holes at the centre of active galactic nuclei (AGN). Their emission is observed across the entire electromagnetic…
Relativistic jets from Active Galactic Nuclei are known since decades, but the study of the connection between accretion and ejection in these systems is hampered by the long time scales associated to these events. The past decade has seen…
Emission-line studies in the active galactic nuclei (AGNs), particularly those utilizing high spatial resolution, provide the most accurate method to determine critical quantities of the central engine and of the gas a few tens of parsecs…
We summarize what large surveys of the contemporary universe have taught us about the physics and phenomenology of the processes that link the formation and evolution of galaxies and their central supermassive black holes. We present a…