Related papers: Can we measure the accretion efficiency of Active …
The determination of the central black hole mass is crucial to the understanding of AGN physics. In this paper we briefly review some methods that are currently used to estimate the black hole mass of AGNs. Particularly we demonstrate the…
Mass accretion rates in dimensionless and physical units, and efficiency factors describing the total radiant luminosity of the disk and the beam power of the outflow are studied here. Four samples of sources including 576 LINERs, 100…
Mass and spin are two fundamental properties of astrophysical black holes. While some established, indirect methods are adopted to measure both these properties of active galactic nuclei (AGN) when viewed relatively face-on, very few…
The bolometric luminosity of active galactic nuclei (AGN) is difficult to determine and various approximations have been used to calibrate it against different observed properties. Here I combine theoretical calculations of optically thick,…
By analogy to the different accretion states observed in black-hole X-ray binaries (BHXBs), it appears plausible that accretion disks in active galactic nuclei (AGN) undergo a state transition between a radiatively efficient and inefficient…
Observations of many dim galactic nuclei in local universe give good estimation of gas density and temperature at Bondi radius. If we assume the black hole accretes at Bondi accretion rate and radiates at efficiency of low-luminosity hot…
Radiative efficiency is an important physical parameter that describes the fraction of accretion material converted to radiative energy for accretion onto massive black holes (MBHs). With the simplest So{\l}tan argument, the radiative…
The radiative efficiency of AGN is commonly estimated based on the total mass accreted and the total AGN light emitted per unit volume in the universe integrated over time (the Soltan argument). In individual AGN, thin accretion disk model…
We investigate the relationship between black hole accretion and star formation in a sample of 453 $z\approx0.3$ type 1 active galactic nuclei (AGNs). We use available CO observations to demonstrate that the combination of nebular dust…
Black hole masses in Active Galactic Nuclei have been determined in 35 objects through reverberation mapping of the emission line region. I mention some uncertainties of the method, such as the ``scale factor'' relating the Virial Product…
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…
In order to find an explanation for the radiative quiescence of supermassive black holes in the local Universe, for a sample of nearby galaxies the most accurate estimates are collected for the mass of a central black hole M_BH, the nuclear…
We investigate the accretion rate, bolometric luminosity, black hole (BH) growth time and BH spin in a large AGN sample under the assumption that all such objects are powered via thin or slim accretion discs (ADs). We use direct estimates…
A supermassive black hole has been found at the centre of nearly every galaxy observed with sufficient sensitivity. The masses of these black holes are observed to increase with either the total mass or the mean (random) velocity of the…
In a recent work we demonstrated that a novel X-ray scaling method, originally introduced for Galactic black holes (GBHs), can be reliably extended to estimate the mass of supermassive black holes accreting at a moderate to high level. Here…
Accretion is the dominant contribution to the cosmic massive black hole density in the Universe today. Yet, modelling it in cosmological simulations is challenging due to the dynamic range involved, as well as the theoretical uncertainties…
We present black hole masses and accretion rates for 182 Type 1 AGN in COSMOS. We estimate masses using the scaling relations for the broad Hb, MgII, and CIV emission lines in the redshift ranges 0.16<z<0.88, 1<z<2.4, and 2.7<z<4.9. We…
Only a small fraction of local galaxies harbor an accreting black hole, classified as an active galactic nucleus (AGN). However, many stellar systems are plausibly expected to host black holes, from globular clusters to nuclear star…
The Bondi accretion rate of black holes in our and nearby galaxies Messier 87, NGC 3115, NGC 1600, and Cygnus A have been determined or constrained using Chandra or other observations. It, however, remains unknown how much mass from the…
We show that the luminosity function of the actively star-forming Lyman break galaxies and the B-band quasar luminosity function at $z = 3$ can be fit reasonably well with the mass function of collapsed galaxy scale dark matter haloes…