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Related papers: Global Slim Accretion Disk Solutions Revisited

200 papers

The formation of the most massive quasars observed at high redshifts requires extreme inflows of gas down to the length scales of the central compact object. Here, we estimate the maximum inflow rate allowed by gravity down to the surface…

High Energy Astrophysical Phenomena · Physics 2021-08-11 L. Haemmerlé , R. S. Klessen , L. Mayer , L. Zwick

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…

Astrophysics · Physics 2007-05-23 Sergei Nayakshin

We investigated flow in Schwarzschild metric, around a non-rotating black hole and obtained self-consistent accretion - ejection solution in full general relativity. We covered the whole of parameter space in the advective regime to obtain…

High Energy Astrophysical Phenomena · Physics 2016-05-04 Indranil Chattopadhyay , Rajiv Kumar

The inward flow of matter through accretion disks is driven by MHD turbulence. Global general relativistic MHD simulations shed quantitative light on this process, revealing a number of aspects of accretion previously unrecognized. Among…

Astrophysics · Physics 2008-11-26 J. H. Krolik , J. F. Hawley

Two-dimensional accretion flows near black holes have been investigated by time-dependent hydrodynamical calculations. We assume that the flow is axisymmetric and that radiative losses of internal energy are negligible, so that the disc is…

Astrophysics · Physics 2015-06-24 Igor V. Igumenshchev , Xingming Chen , Marek A. Abramowicz

Accretion is the dominant contribution to the cosmic massive black hole density in the Universe today. Yet, modelling it in cosmological simulations is challenging due to the dynamic range involved, as well as the theoretical uncertainties…

We study low-density axisymmetric accretion flows onto black holes (BHs) with two-dimensional hydrodynamical simulations, adopting the $\alpha$-viscosity prescription. When the gas angular momentum is low enough to form a rotationally…

Astrophysics of Galaxies · Physics 2018-09-18 Kohei Inayoshi , Jeremiah P. Ostriker , Zoltan Haiman , Rolf Kuiper

Slim accretion disks idea emerged over 30 years ago as an answer to several unsolved problems. Since that time there was a tremendous increase in the amount of observational data where this model applies. However, many critical issues on…

Astrophysics of Galaxies · Physics 2019-05-22 Bozena Czerny

We present a systematic, analytical study of geometrically thin, optically thick accretion disc solutions for magnetized turbulent flows, with an alpha-like viscosity prescription. Under the only assumptions that (1) Magneto-Rotational…

Astrophysics · Physics 2009-11-07 A. Merloni

It is widely believed that super-Eddington accretion flow can produce powerful outflow, but where it originates from and how much mass and energy are carried away to which directions? To answer to these questions, we newly perform a…

High Energy Astrophysical Phenomena · Physics 2021-02-03 Takaaki Kitaki , Shin Mineshige , Ken Ohsuga , Tomohisa Kawashima

A new one-dimensional, dynamical model is proposed for geometrically thin, self-gravitating viscous accretion discs. The vertically integrated equations are simplified using the slow accretion limit and the monopole approximation with a…

Astrophysics of Galaxies · Physics 2015-04-30 Tobias F. Illenseer , Wolfgang J. Duschl

Photon trapping and outflow are two key physics associated with the supercritical accretion flow. We investigate the conflict between these two processes based on two-dimensional radiation-hydrodynamic (RHD) simulation data and construct a…

High Energy Astrophysical Phenomena · Physics 2015-05-13 Shun Takeuchi , Shin Mineshige , Ken Ohsuga

We present an approach to deriving global properties of accretion disks from the knowledge of local solutions derived from numerical simulations based on the shearing box approximation. The approach consists of a two-step procedure. First a…

Solar and Stellar Astrophysics · Physics 2016-03-02 G. Bodo , F. Cattaneo , A. Mignone , F. Ponzo , P. Rossi

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…

Astrophysics · Physics 2009-06-23 Zdenka Kuncic , Geoffrey V. Bicknell

When gas accretes onto a black hole, at a rate either much less than or much greater than the Eddington rate, it is likely to do so in an "adiabatic" or radiatively inefficient manner. Under fluid (as opposed to MHD) conditions, the disk…

Astrophysics · Physics 2009-11-07 Roger D. Blandford , Mitchell C. Begelman

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…

Astrophysics · Physics 2008-11-26 J. F. Hawley , J. -P. De Villiers

We study accretion rates during the gravitational wave-driven merger of a binary supermassive black hole embedded in an accretion disc, formed by gas driven to the centre of the galaxy. We use 3D simulations performed with PHANTOM, a…

High Energy Astrophysical Phenomena · Physics 2016-02-03 Alice Cerioli , Giuseppe Lodato , Daniel J. Price

A near-equal mass binary black hole can clear a central cavity in a circumbinary accretion disk; however, previous works have revealed accretion streams entering this cavity. Here we use 2D hydrodynamical simulations to study the accretion…

Astrophysics of Galaxies · Physics 2013-10-22 Daniel J. D'Orazio , Zoltán Haiman , Andrew MacFadyen

We study the solution of viscous accretion disks around rotating compact/central object having hard surface i.e. neutron star, strange star and any other highly gravitating objects. We choose pseudo-Newtonian approach to describe the…

Astrophysics · Physics 2009-11-07 Banibrata Mukhopadhyay , Shubhrangshu Ghosh

We compare different examples of spherical accretion onto a gravitating mass. Limiting cases include the accretion of a collisionally dominated fluid and the accretion of collisionless particles. We derive expressions for the accretion rate…

Astrophysics · Physics 2009-11-11 Re'em Sari , Peter Goldreich