Related papers: Magnetically-levitating disks around supermassive …
We summarize results from a survey of radiation-dominated black hole accretion flows across a wide range of mass accretion rates, as well as two values of black hole spin and initial magnetic field geometry. These models apply an algorithm…
Qualitative arguments are presented to demonstrate that the energy density of magnetic fields in matter accreting onto a black hole inside the marginally stable orbit is automatically comparable to the rest-mass energy density of the…
We examine the evolution and influence of viscosity-induced diskoseismic modes in simulated black hole accretion disks. Understanding the origin and behavior of such oscillations will help us to evaluate their potential role in producing…
We present a set of three-dimensional, global, general relativistic radiation magnetohydrodynamic simulations of thin, radiation-pressure-dominated accretion disks surrounding a non-rotating, stellar-mass black hole. The simulations are…
Combined influence of rotation of a black hole and ambient magnetic fields creates conditions for powerful astrophysical processes of accretion and outflow of matter which are observed in many systems across the range of masses; from…
Accretion disks, swirling structures of matter spiraling into black holes, play a pivotal role in our understanding of binary star systems and their intricate evolutionary processes. While current models often simplify these complex…
Winds from black hole accretion disks are essential ingredients in understanding the coevolution between the supermassive black hole and its host galaxy. The great difference of dynamical ranges from small-scale accretion disk simulations…
We conduct a systematic study of the properties of tilted accretion flows around spinning black holes, covering a range of tilt angles and black hole spins, using the general-relativistic magnetohydrodynamics code Athena++. The same initial…
We present global magnetohydrodynamic (MHD) simulations of accretion disks with a strong toroidal magnetic field using an equation of state that fixes the gas thermal scale height. The disk forms from the inflow of a rotating magnetized gas…
We consider the combined role of the thermal ionization, magneto-rotational and gravitational instabilities in thin accretion disks around supermassive black holes. We find that in the portions of the disk unstable to the ionization…
Magnetically arrested accretion discs (MADs) around black holes (BH) have the potential to stimulate the production of powerful jets and account for recent ultra-high-resolution observations of BH environments. Their main properties are…
We present simulations of thin accretion disks around black holes investigating a mean-field disk dynamo in our resistive GRMHD code (Vourellis et al. 2019) that is able to produce a large scale magnetic flux. We consider a weak seed field…
Massive primordial halos exposed to moderate UV backgrounds are the potential birthplaces of supermassive black holes. In such a halo, an initially isothermal collapse will occur, leading to high accretion rates of…
A magnetic field dynamo in the inner regions of the accretion disk surrounding the supermassive black holes in AGNs may be the mechanism for the generation of magnetic fields in galaxies and in extragalactic space. We argue that the two…
In this paper, we report on the first 3D general relativistic radiation magnetohydrodynamic simulations of large supercritical accretion discs that are tilted with respect to the black hole spin axis. We explore a range of black hole spin…
(Abridged) We study the dynamical evolution of a stationary, axisymmetric, and perfectly conducting cold accretion disk containing a large-scale magnetic field around a Kerr black hole, trying to understand the relation between accretion…
We propose that the accretion disks fueling active galactic nuclei are supported vertically against gravity by a strong toroidal ($\phi-$direction) magnetic field that develops naturally as the result of an accretion disk dynamo. The…
Recent studies have focused on how spinning black holes (BHs) within a binary system containing a strongly magnetized neutron star, then immersed in external magnetic fields, can acquire charge through mechanisms like the Wald process and…
We theoretically investigate the magnetic flux transport in geometrically thick accretion discs which may form around black holes. We utilize a two-dimensional (2D) kinematic mean-field model for poloidal field transport which is governed…
A selection of results from the general relativistic MHD accretion simulations described in the previous talk are presented. We find that the magnetic field strength increases sharply with decreasing radius and is also enhanced near…