Related papers: Accretion and ejection in black-hole X-ray transie…
We report results from a systematic study of X-ray emission from black hole transients in quiescence. In this state mass accretion is thought to follow the geometry of an outer optically thick, geometrically thin disc and an inner optically…
Magnetized accretion onto spinning black holes can accumulate a large magnetic flux across the event horizon and launch a pair of relativistic jets via the Blandford-Znajek mechanism. In the magnetically saturated (arrested) state, excess…
In this paper, we examine the motion of test particles and relativistic accretion mechanisms within the spacetime of a rotating and embedded BH. In this case, the geometric properties of the metric and their dynamical consequences for…
Most black holes (BHs) formed in collapsing stars have low spin, though some are expected to acquire a magnetic accretion disk during the collapse. While such BH disks can launch magnetically driven winds, their physics and observational…
We study the transport of baryons in magnetically arrested accretion flows and relativistic jets using general relativistic magnetohydrodynamic simulations that incorporate a passive Eulerian tracer. The tracer allows us to reconstruct a…
The dynamics of a black hole traveling through a plasma--a general relativistic extension of the classic Bondi-Hoyle-Lyttleton (BHL) accretion problem--can be related to a variety of astrophysical contexts, including the aftermath of binary…
Black hole binaries exhibit dramatic changes in their X-ray spectral and timing properties over time, providing important clues about the physical processes that occur in these systems. Black holes and black hole candidates are prime…
We briefly review recent developments in black hole accretion disk theory, placing new emphasis on the vital role played by magnetohydrodynamic (MHD) stresses in transporting angular momentum. The apparent universality of accretion-related…
We briefly review recent developments in black hole accretion disk theory, emphasizing the vital role played by magnetohydrodynamic (MHD) stresses in transporting angular momentum. The apparent universality of accretion-related outflow…
Hyperaccretion occurs when the gas inflow rate onto a black hole (BH) is so high that the radiative feedback cannot reverse the accretion flow. This extreme process is a promising mechanism for the rapid growth of seed BHs in the early…
The exact time-dependent solution is obtained for a magnetic field growth during a spherically symmetric accretion into a black hole (BH) with a Schwarzschild metric. Magnetic field is increasing with time, changing from the initially…
The radiative efficiency of super-Eddington accreting black holes (BHs) is explored for magnetically-arrested disks (MADs), where magnetic flux builds-up to saturation near the BH. Our three-dimensional general relativistic radiation…
In this review, I summarize the main X-ray/hard X-ray properties of the accretion flows around black holes and neutron stars based on recent broad-band spectral and timing observations performed by the BeppoSAX and Rossi X-ray Timing…
Magnetic fields regulate black hole (BH) accretion, governing both inflow and outflow dynamics. When a BH accumulates substantial vertical magnetic flux, it enters the magnetically arrested disk (MAD) state, where dynamically important…
Outflows are inevitably driven from the disk if the vertical component of the black hole (BH) gravity cannot resist the radiation force. We derive the mass loss rate in the outflows by solving a dynamical equation for the vertical gas…
To understand the decaying phase of outbursts in the black hole (BH) X-ray binaries (BH-XRBs), we performed very long general relativistic magneto-hydrodynamic (GRMHD) simulations of a geometrically thin accretion disk around a Kerr BH with…
The X-ray spectra of black hole binaries in the low/hard state first harden as the flux decreases, then soften. This change in behaviour has been variously attributed to either the X-rays switching from being produced in the flow to being…
Spinning supermassive black holes (BHs) in active galactic nuclei (AGN) magnetically launch relativistic collimated outflows, or jets. Without angular momentum supply, such jets are thought to perish within $3$ orders of magnitude in…
Our X-ray study of the nuclear activity in a new sample of six quiescent early-type galaxies, and in a larger sample from the literature, confirmed (Soria et al., Paper I) that the Bondi accretion rate of diffuse hot gas is not a good…
We studied the relation of accretion-jet power and disk luminosity, especially the jet efficiencies and disk radiative efficiencies for different accretion disks as well as black hole (BH) spin, in order to explore the origin of radio…