相关论文: Accretion Discs Around Black Holes: Developement o…
I outline the theory of accretion onto black holes, and its application to observed phenomena such as X-ray binaries, active galactic nuclei, tidal disruption events, and gamma-ray bursts. The dynamics as well as radiative signatures of…
We present the detailed global structure of black hole accretion flows and outflows through newly performed two-dimensional radiation-magnetohydrodynamic simulations. By starting from a torus threaded with weak toroidal magnetic fields and…
We discuss the properties of an accretion disk around a star with parameters typical of classical T Tauri stars (CTTS), and with the average accretion rate for these disks. The disk is assumed steady and geometrically thin. The turbulent…
Two related topics are discussed. 1. Accretion onto black holes at low and high (though not very high) rates is believed to proceed adiabatically ({\em ie} non-radiatively). It is argued that the liberated energy is carried off by an…
We study the accretion flow of a hot gas captured by the black hole gravity in the presence of a thin cold accretion disk. Such geometrical arrangement is expected in Active Galactic Nuclei (AGN) and in galactic X-ray binary systems because…
The inner boundary of a black hole accretion disk is often set to the marginally stable circular orbit (or the innermost stable circular orbit, ISCO) around the black hole. It is important for the theories of black hole accretion disks and…
Nonlinear time-dependent calculations have been carried out in order to study the evolution of the thermal instability for optically thick, transonic, slim accretion discs around black holes. In the present calculations we have investigated…
We review the current understanding of accretion flows around compact objects with a special emphasis on advective disks. We discuss the influence of the centrifugal pressure supported high density region around compact objects (where…
We describe new optically thin solutions for rotating accretion flows around black holes and neutron stars. These solutions are advection dominated, so that most of the viscously dissipated energy is advected radially with the flow. We…
Recently, the issue of the role of the Eddington limit in accretion discs became a matter of debate. While the classical (spherical) Eddington limit is certainly an over-simplification, it is not really clear how to treat it in a flattened…
We develop and discuss a model formalism to study the properties of mass outflows that are emerged out from a relativistic, magnetized, viscous, advective accretion flow around a rotating black hole. In doing so, we consider the toroidal…
We investigate the model of the disc/corona accretion flow around the black hole. The model, parameterized by the total (i.e. disk plus corona) accretion rate, $\dot m$, mass of the black hole, $M$ and the viscosity parameter, $\alpha$,…
Most black holes possess accretion disks. Models of such disks inform observations and constrain the properties of the black holes and their surrounding medium. Here, we study isothermal shocks in a thin black hole accretion flow. Modelling…
We present an analytic description of turbulent, MHD disk accretion around black holes that specifically addresses the relationship between radial and vertical, transport, thereby complementing and extending numerical simulations. The…
A relativistic model of geometrically thin and optically thick accretion disks is worked out for a class of magnetically charged black holes, which are solutions to the Einstein-Maxwell-dilaton theory with a dilaton-coupled Euler-Heisenberg…
The effect of an accretion disk on the Blandford-Znajek process and the evolution of a black hole are discussed using a simplified system for the black hole - accretion disk in which the accretion rate is supposed to be dominated by the…
Disc accretion on to a black hole is often misaligned from its spin axis. If the disc maintains a significant magnetic field normal to its local plane, we show that dipole radiation from Lense-Thirring precessing disc annuli can extract a…
We present solutions to the accretion disk structure equations in which advective cooling is accounted for in a self-consistent way. It is shown that for high rates of accretion, above a critical value, when without advection there are no…
This paper presents a continuation of our efforts to numerically study accretion disks that are misaligned (tilted) with respect to the rotation axis of a Kerr black hole. Here we present results of a global numerical simulation which fully…
We investigate accretion onto an isolated black hole from uniform winds. If the winds are directed towards the black hole, then the accretion process can be well described by the classical Bondi-Hoyle Lyttleton or BHL accretion. If the wind…