Related papers: Dormant black holes tell a story about the evoluti…
We derive the mass function of the relic black holes and compared with that of the Massive Dark Objects in galaxies. Under the assumption that accretion onto massive BH's powers the Active Galactic Nuclei, the mass function of the BH…
It has long been suspected that Active Galactic Nuclei are powered by accretion of matter onto massive black holes and this belief implies their presence in the nuclei of most nearby galaxies as "relics" of past activity. Just a few years…
Massive black holes are key inhabitants of the nuclei of galaxies. Moreover, their astrophysical relevance has gained significant traction in recent years, thanks especially to the amazing results that are being (or will be) delivered by…
This article gives a brief overview of the direct and indirect evidence in support of the standard paradigm that active galactic nuclei are powered by supermassive black holes.
A significant fraction of local galaxies show evidence of nuclear activity. I argue that the bulk of this activity, while energetically not remarkable, derives from accretion onto a central massive black hole. The statistics of nearby…
The black hole mass function of supermassive black holes describes the evolution of the distribution of black hole mass. It is one of the primary empirical tools available for mapping the growth of supermassive black holes and for…
Supermassive black holes inhabit galactic nuclei, and their presence influences in crucial ways the evolution of the stellar distribution. The low-density cores observed in bright galaxies are probably a result of black hole infall, while…
A variety of observational approaches have provided evidence for extended halos of dark matter surrounding elliptical galaxies, and for massive dark objects in (some of) their nuclei. What are the properties of the dark halos? How do they…
In the past decade, much effort was devoted to measure the masses of supermassive black holes in galactic nuclei, to establish the relation between black hole mass and the global/nuclear properties of the host galaxy, and to understand the…
The supermassive black holes harboured in active galactic nuclei are at the origin of powerful jets which can emit copious amounts of gamma-rays. The exact interplay between the infalling matter, the black hole and the relativistic outflow…
This paper summarizes the observations which provide the best evidence for the presence of black holes in active galactic nuclei. This includes: X-ray variability; kinematical studies using optical emission lines as well as the distribution…
I review the status of observational determinations of central masses in nearby galactic nuclei. Results from a variety of techniques are summarized, including ground-based and space-based optical spectroscopy, radio VLBI measurements of…
Massive black holes are ubiquitous, occurring at the centres of all massive galaxies and possibly many low mass ones. They are no ornament which just happens to be there, but play a role vital to the growth and structure of the host galaxy.…
The masses of the central black holes of Active Galactic Nuclei estimated by the reverberation virial technique seem to be significantly smaller than predicted from the black hole mass-bulge luminosity relation for massive black holes…
Almost every galaxy in the local Universe is observed to have a massive black hole in the centre. The properties of these black holes are observed to tightly correlate with those of their host galaxy which has been interpreted as…
Since a black hole does not emit light from its interior, nor does it have a surface on which light from nearby sources can be reflected, observational study of black hole physics requires observing the gravitational impact of the black…
Supermassive black holes containing ~0.5% of the stellar mass of their host galaxies appear to be ubiquitous components of galactic nuclei. The gravitational force from these central singularities can influence the motion of stars far…
We report the first results of a program to measure accurate stellar velocity dispersions in the bulges of the host galaxies of active galactic nuclei (AGNs) for which accurate black hole (BH) masses have been determined via reverberation…
Considerable observational evidence suggests that the activity of supermassive black holes in galactic nuclei is transient. The term ``active galactic nuclei archaeology'' has even been coined. This implies the possibility of reconstructing…
The article summarizes the observational evidence for the existence of massive black holes, as well as the current knowledge about their abundance, their mass and spin distributions, and their cosmic evolution within and together with their…