Related papers: Magnetic Fields of Black Holes and the Variability…
Non-ideal MHD effects may play a significant role in determining the dynamics, thermal properties, and observational signatures of radiatively inefficient accretion flows onto black holes. In particular, particle acceleration during…
We solved the set of two-dimensional magnetohydrodynamic (MHD) equations for optically thin black hole accretion flows incorporating toroidal component of magnetic field. Following global and local MHD simulations of black hole accretion…
The efficiency of thin disk accretion onto black holes depends on the inner boundary condition, specifically the torque applied to the disk at the last stable orbit. This is usually assumed to vanish. I estimate the torque on a magnetized…
We show that Massive Black Holes of AGNs follow the same approximately linear relation with the luminosity of the host spheroid (bulge) found in normal (quiescent) galaxies, with the black hole mass being ~0.002 that of the bulge. We also…
In this Letter we use a simple model to demonstrate the observational signatures of the magnetic connection between a black hole and a disk: (1) With the magnetic connection more energy is dissipated in and radiated away from regions close…
Observations indicate that wind can be generated in hot accretion flow. By performing numerical simulations, Yuan et al. studied the detailed properties of wind generated from weakly magnetized accretion flow. However, properties of wind…
If a magnetically dominated magnetosphere is to extract a black hole's rotational energy and transmit it to distant regions, then the inner light surface of that magnetosphere must lie within the ergoregion. That inner light surface…
We discuss the emergent spectra from accreting black holes, considering in particular the case where the accretion is characterized by relativistic bulk motion. We suggest that such accretion is likely to occur in a wide variety of black…
Using long-duration general relativistic magnetohydrodynamic simulations of radiatively inefficient accretion discs, the energy, momentum and mass outflow rates from such systems are estimated. Outflows occur via two fairly distinct modes:…
We investigate where brightest cluster galaxies (BCGs) sit on the fundamental plane of black hole (BH) activity, an established relation between the X-ray luminosity, the radio luminosity and the mass of a BH. Our sample mostly consists of…
The electromagnetic field near a rotating black hole is being explored in educational style here. By employing analytic solutions for electrovacuum fields, we plot the surfaces of constant flux and we show how the field is dragged around…
We present general relativistic radiation MHD simulations of super-Eddington accretion on a $10M_\odot$ black hole. We consider a range of mass accretion rates, black hole spins, and magnetic field configurations. We compute the spectra and…
We present a model for the short timescale spectral variability of accreting black holes. It describes well the time-averaged spectra as well as temporal characteristics such as power-density spectrum, time/phase lags, and coherence…
We consider weakly magnetized non-rotating black holes. In the presence of a regular magnetic field the motion of charged particles in the vicinity of a black hole is modified. As a result, the position of the innermost stable circular…
Both theoretical models and observational evidence indicate that jets and/or outflows driven by central active supermassive black holes exert a significant feedback effect on the overall properties of their host galaxies. Theoretical models…
The exact two-dimensional non-stationary solution for the evolution of the magnetic field during accretion with nearly spherical symmetry, using Newton's solution and considering both Keplerian and sub-Keplerian flows around the black hole…
We investigate the relation of black hole mass versus host stellar mass and that of mass accretion rate versus star formation rate (SFR) in moderately luminous ($\log L_{\rm bol} \sim 44.5-46.5\ {\rm erg\ s^{-1}}$), X-ray selected…
We present new and stronger evidence for a previously reported relationship between galactic spiral arm pitch angle P (a measure of the tightness of spiral structure) and the mass M_BH of a disk galaxy's nuclear supermassive black hole…
The gravitational wave signature of a binary black hole (BBH) merger is dependent on its component mass and spin. If such black holes originate from rapidly rotating progenitors, the large angular momentum reserve in the star could drive a…
The magnetic field structure of a star-forming Bok globule BHR 71 was determined based on near-infrared polarimetric observations of background stars. The magnetic field in BHR 71 was mapped from 25 stars. By using a simple 2D parabolic…