Related papers: Some Comments related to AGN Radio Loudness
Multiwavelength variability data, combined with spectral-timing analysis techniques, provides information about the causal relationship between different physical components in accreting black holes. Using fast-timing data and long-term…
A radio bimodality is observed in galaxy clusters: a fraction of clusters host giant radio halos while the majority of clusters do not show evidence of diffuse cluster-scale radio emission. Present data clearly suggest that the radio…
They are weak, they are small, and they are often overlooked, but they are numerous and an ubiquitous sign of accreting black holes: compact radio cores and jets in low-power AGN. Here I summarize our work concerning these radio cores and…
Three recent papers have been collected here, discussing the possibility and properties of periodic modulation of a signal from accreting black holes surrounded by orbiting clumps of gas.
The masses of the central black holes in Active Galactic Nuclei (AGNs) can be estimated using the broad emission-lines as a probe of the virial mass. Using reverberation mapping to determine the size of the Broad Line Region (BLR) and the…
The hypothesis that the mass of black holes increases with time according to the same law as the volume of the part of the Universe containing it and therefore the population of BHs is similar to dark energy in its action was recently…
We take the established relation between black hole mass, X-ray luminosity, and radio luminosity and show that intermediate mass black holes, such as those predicted to exist at the centers of globular clusters, will be easily identifiable…
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…
Ongoing and future radio surveys aim to trace the evolution of black hole growth and feedback from active galactic nuclei (AGN) throughout cosmic time; however, there remain major uncertainties in translating radio luminosity functions into…
The connection between normal and active galaxies is reviewed, by summarizing our progress on answering nine key questions. (1) Do all galaxies contain massive dark objects (MDOs)? (2) Are these MDOs actually supermassive black holes? (3)…
Relativistic jets are one of the most powerful manifestations of the release of energy produced around supermassive black holes at the centre of active galactic nuclei (AGN). Their emission is observed across the entire electromagnetic…
We use a large, heterogeneous sample of local active galactic nuclei (AGN) that includes Seyfert 1s, Seyfert 2s and PG quasars to investigate for the first time the relation between black hole mass (M_BH) and mid-infrared nuclear emission.…
We have studied the relationship between the nuclear (high-resolution) radio emission, at 8.4 GHz (3.6 cm) and 1.4 GHz (20 cm), the [O IV] 25.89um, [Ne III] 15.56um and [Ne II] 12.81um emission lines and the black hole mass accretion rate…
Black holes with masses M_BH~10^{8.5} M_Sun dominate the accretion history of the Universe. These black hole masses are typical of those found in radio-selected galaxies today, suggesting that the giant elliptical hosts of low redshift…
Studying the morphology of a large sample of active galaxies at different wavelengths and comparing it with active galactic nuclei (AGN) properties, such as black hole mass ($M_{BH}$) and Eddington ratio ($\lambda_{Edd}$), can help us in…
We investigate the relation between black hole mass, M_bh, and jet power, Q_jet, for a sample of BL Lacs and radio quasars. We find that BL Lacs are separated from radio quasars by the FR I/II dividing line in M_bh-Q_jet plane, which…
Black hole accretion and jet production are areas of intensive study in astrophysics. Recent work has found a relation between radio luminosity, X-ray luminosity, and black hole mass. With the assumption that radio and X-ray luminosity are…
The appearance of active galactic nuclei (AGN) depends so strongly on orientation that our current classification schemes are dominated by random pointing directions instead of more interesting physical properties. Light from the centers of…
We summarize the results from numerical simulations of mass outflows from AGN. We focus on simulations of outflows driven by radiation from large-scale inflows. We discuss the properties of these outflows in the context of the so-called AGN…
Giant radio galaxies are thought to be massive ellipticals powered by accretion of interstellar matter onto a supermassive black hole. Interactions with gas rich galaxies may provide the interstellar matter to feed the active galactic…