相关论文: Interpreting radiative efficiency in radio-loud AG…
We address the very large diversity of the jet production efficiency in active galactic nuclei (AGNs) by using data on low redshift AGNs selected from the Swift/BAT catalog and having black hole (BH) masses larger than…
We consider the distribution of local supermassive black hole Eddington ratios and accretion rates, accounting for the dependence of radiative efficiency and bolometric corrections on the accretion rate. We find that black hole mass growth,…
We perform a set of general relativistic, radiative, magneto-hydrodynamical simulations (GR-RMHD) to study the transition from radiatively inefficient to efficient state of accretion on a non-rotating black hole. We study ion to electron…
We have studied the nuclear emission detected in high-resolution radio and optical data of carefully selected samples of low luminosity AGN (LLAGN) in the local universe. When the Eddington ratio is plotted against the nuclear…
For the first time in literature, we provide an exact analytical scheme for calculating the analogous Hawking temperature and surface gravity for general relativistic accretion onto astrophysical black holes. Our calculation may bridge the…
[abridged] AGN feedback is a crucial ingredient for understanding galaxy evolution. However, a complete quantitative time-dependent framework, including the dependence of such feedback on AGN, host galaxy, and host halo properties, is yet…
In recent work, we have identified two sub-populations of radio-loud AGN which appear to be distinguished by jet structure, where low-efficiency accreting systems produce `weak' jets which decelerate more rapidly than the `strong' jets of…
A recent analysis of black hole scaling relations, used to estimate the local mass density in black holes, has indicated that the normalization of the scaling relations should be increased by approximately a factor of five. The local black…
We argue that the magnetic flux threading the black hole, rather than black hole spin or Eddington ratio, is the dominant factor in launching powerful jets and thus determining the radio loudness of active galactic nuclei (AGN). Most AGN…
We derived the black hole fundamental plane relationship among the 1.4GHz radio luminosity (L_r), 0.1-2.4keV X-ray luminosity (L_X), and black hole mass (M) from a uniform broad line SDSS AGN sample including both radio loud and radio quiet…
In large scale cosmological hydrodynamic simulations simplified sub-grid models for gas accretion onto black holes and AGN feedback are commonly used. Such models typically depend on various free parameters, which are not well constrained.…
Accreting black holes and neutron stars at luminosities above 0.01 of the critical Eddington luminosity have a lot of similarities, but also drastic differences in their radiation and power density spectra. The efficiency of energy release…
This article reports on a growing body of observational evidence that many powerful lobe dominated (FR II) radio sources likely have jets with high efficiency. This study extends the maximum efficiency line (jet power $\approx$ 25 times the…
We recently argued (Meyer 2011) that the collective properties of radio loud active galactic nuclei point to the existence of two families of sources, one of powerful sources with single velocity jets and one of weaker jets with significant…
We present here a new determination of the ratio of energies radiated by active galactic nuclei and by stars and discuss the reasons for the apparently conflicting results found in previous studies. We conclude that the energy radiated by…
An empirical relation between the broad line region (BLR) size and optical continuum luminosity is often adopted to estimate the BLR size and then the black hole mass of AGNs. However, optical luminosity may not be a good indicator of…
Combined investigations of the clustering properties of galaxies of different spectral type and high-redshift quasars strongly suggest local ellipticals to be the parent population of optically bright Active Galactic Nuclei (AGN). However,…
The idea of a unified description of supermassive and stellar black holes has been supported by the extension of the empirical radio/X-ray correlation from X-ray binaries to active galactic nuclei through the inclusion of a mass term. This…
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…
We investigate the dichotomy between jetted and non-jetted Active Galactic Nuclei (AGNs), focusing on the fundamental differences of these two classes in the accretion physics onto the central supermassive black hole (SMBH). Our aim is to…