Related papers: Linking the central engine to the jet properties i…
(abridged) The connection between black hole, accretion disk, and radio jet can be best constrained by fitting models to observations of nearby low luminosity galactic nuclei, in particular the well studied sources Sgr~A* and M87. There has…
An introduction is given to a meeting on the role of massive and stellar black holes in powering non-thermal activity in a rich variety of cosmic sources. Relevant properties of magnetized, spinning black holes are summarized and their…
The long-term variability study over a range of black hole (BH) mass systems from the microquasars of stellar-mass black holes to the Active Galactic Nuclei (AGNs) of supermassive black holes, in $\gamma$-rays offers new insights into the…
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…
The scaling relations between supermassive black holes and their host galaxy properties are of fundamental importance in the context black hole-host galaxy co-evolution throughout cosmic time. In this work, we use a novel algorithm that…
Relativistic jets are collimated plasma outflows with relativistic speeds. Astrophysical objects involving relativistic jets are a system comprising a compact object such as a black hole, surrounded by rotating accretion flows, with the…
From Liu and Han (2014), the accretion-dominated jet power has a linear proportionality with the accretion rate, whereas the power law index is <=0.5 at lower accretion rate. Attributing the jet power in low accretion rate AGN to the black…
We use the observed jet boundary transition from parabolic to conical shape, which was earlier discovered as possibly a common effect in active galactic nuclei, to estimate a black hole, a jet and an ambient medium parameters. We explained…
We present results from infrared spectroscopic projects that aim to test the relation between the mass of a black hole, M_BH, and the velocity dispersion of the stars in its host-galaxy bulge. We demonstrate that near-infrared,…
The black hole MAXI J1820+070 was discovered during its 2018 outburst and was extensively monitored across the electromagnetic spectrum. Following the detection of relativistic radio jets, we obtained four Chandra X-ray observations taken…
Reverberation mapping methods have been used to measure masses in about three dozen AGNs. The consistency of the virial masses computed from line widths and time delays, the relationship between black hole mass and host-galaxy stellar bulge…
The current understanding of the formation of powerful bi-directional jets in systems such as radio galaxies and quasars is that the process involves a supermassive black hole that is being fed with magnetized gas through an orbiting…
We have assembled a sample of 37 RLQs that have been imaged with the HST in order to investigate their black hole masses, accretion rates, and the structure of their accretion disks. The black hole masses were estimated from the…
What causes the dichotomy between very powerful and very weak radio emission from AGNs? Perhaps the engines are the same but the jets get disrupted by dense ISM in radio-quiet objects, or else the engines are intrinsically different with…
In the present-day universe, supermassive black hole masses (MBH) appear to be strongly correlated with their galaxy's bulge luminosity, among other properties. In this study, we explore the analogous relationship between MBH, derived using…
By combining the recently derived X-ray luminosity function for Galactic X-ray binaries (XRBs) by Grimm et al. (2002) and the radio-X-ray-mass relation of accreting black holes found by Merloni et al. (2003), we derive predictions for the…
Black hole mass is a key factor in determining how a black hole interacts with its environment. However, the determination of black hole masses at high redshifts depends on secondary mass estimators, which are based on empirical…
We investigate the connection between supermassive black holes (SMBHs), their host galaxies, and large-scale dark-matter halos using broad-line X-ray AGN from the XMM--XXL and Stripe\,82X surveys, together with galaxies from VIPERS and…
It is still a mystery why only a small fraction of active galactic nuclei (AGNs) contain relativistic jets. Strong magnetic field is a necessary ingredient for jet formation, however, the advection of the external field in a geometrically…
The new high energy data coming mainly from the Fermi and Swift satellites and from the ground based Cerenkov telescopes are making possible to study not only the energetics of blazar jets, but also their connection to the associated…