Related papers: Magnetically-levitating disks around supermassive …
A spinning black hole accreting from a disk of strongly magnetized plasma via a magnetically arrested disk is known to produce an efficient electromagnetic jet powered by the black hole's spin energy. We present general relativistic…
Observations are providing increasingly detailed quantitative information about the accretion flows that power such high energy systems as X-ray binaries and active galactic nuclei. Analytic models of such systems must rely on assumptions…
Recent results of the event horizon-scale images of M87* and Sagittarius A* from the Event Horizon Telescope Collaboration show that strong magnetic fields are likely present around the central black holes (BHs) in these sources.…
We posit that accreting compact objects, including stellar mass black holes and neutron stars as well as supermassive black holes, may undergo extended periods of accretion during which the angular momentum of the disk at large scales is…
We present three-dimensional magnetohydrodynamic (MHD) simulations of the fueling of supermassive black holes in elliptical galaxies from a turbulent cooling medium on galactic scales, taking M87* as a typical case. We find that the mass…
Multiple models have been suggested over the years to explain the structure and support of accretion disks around supermassive black holes, from the standard thin thermal-pressure-dominated $\alpha$-disk model to more recent models that…
Large-scale magnetic fields in the nuclear regions of protogalaxies can promote the formation and early growth of supermassive black holes (SMBHs) by direct collapse and magnetically boosted accretion. Turbulence associated with…
In this chapter, we review some of the interesting consequences that tilt between the spin axis of the black hole and angular momentum axis of the accretion disk can have on the dynamics, thermodynamics, and observational appearance of…
We model numerically the evolution of $10^4M_\odot$ turbulent molecular clouds in near-radial infall onto $10^6M_\odot$, equal-mass super-massive black hole binaries, using a modified version of the SPH code GADGET-3. We investigate the…
Disk accretion may be the fundamental astrophysical process. Stars and planets form through the accretion of gas in a disk. Black holes and galaxies co-evolve through efficient disk accretion onto the central supermassive black hole.…
We present a novel approach to study the global structure of steady, axisymmetric, advective, geometrically thin, magnetohydrodynamic (MHD) accretion flow around black holes in full general relativity (GR). Considering ideal MHD conditions…
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…
Black holes attract gaseous material from the surrounding environment. Cosmic plasma is largely ionized and magnetized because of electric currents flowing in the highly conductive environment near black holes; the process of accretion then…
The origin of the rapid quasi-periodic variabilities observed in a number of accreting black hole X-ray binaries is not understood. It has been suggested that these variabilities are associated with diskoseismic oscillation modes of the…
We investigate stationary models of magnetized, self-gravitating disks around black holes. The disks are assumed to rotate according to a recently introduced Keplerian rotation law. We consider different prescriptions of the toroidal…
Direct collapse black holes (DCBHs) are the leading candidates for the origin of the first supermassive black holes. However, the role of magnetic fields during their formation is still unclear as none of the previous studies has been…
Standard accretion disk theory is formulated which is based on the local heat balance. The energy produced by a turbulent viscous heating is supposed to be emitted to the sides of the disc. Sources of turbulence in the accretion disc are…
Accretion in the nuclei of active galaxies may occur chaotically. This can produce accretion discs which are counter-rotating or strongly misaligned with respect to the spin of the central supermassive black hole (SMBH), or the axis of a…
There is compelling evidence that most -if not all- galaxies harbour a super-massive black hole (SMBH) at their nucleus, hence binaries of these massive objects are an inevitable product of the hierarchical evolution of structures in the…
We show that accretion disks with magnetic fields in them ought to make jets provided that their electrical conductivity prevents slippage and there is an ambient pressure in their surroundings. We study equilibria of highly wound magnetic…