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Related papers: A Note on Bimodal Accretion Disks

200 papers

We study stationary and axially symmetric black hole-disk systems, assuming a combination of the DD2 and Timmes-Swesty equations of state and a three-parameter family of rotation laws. There exist two branches of solutions that are shown to…

General Relativity and Quantum Cosmology · Physics 2021-07-07 Wojciech Kulczycki , Patryk Mach , Edward Malec

Accretion discs are composed of ionized gas in motion around a central object. Sometimes, the disc is the source of powerful bipolar jets along its rotation axis. Theoretical models invoke the existence of a bipolar magnetic field crossing…

High Energy Astrophysical Phenomena · Physics 2011-12-23 Remi de Guiran , Jonathan Ferreira

Ultraluminous X-ray sources fed by Wolf-Rayet star winds and X-ray bursters in ultracompact binaries with He or C white dwarfs have accretion disks, whose properties may significantly differ from those of pure H alpha-accretion disks. We…

Astrophysics · Physics 2007-05-23 J. Dunkel , J. Chluba , R. A. Sunyaev

We show that most of hot, optically thin accretion disk models which ignore advective cooling are not self-consistent. We have found new types of optically thin disk solutions where cooling is dominated by radial advection of heat. These…

Astrophysics · Physics 2009-10-22 Marek A. Abramowicz , Xingming Chen , Shoji Kato , Jean-Pierre Lasota , Oded Regev

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…

Astrophysics · Physics 2009-10-22 Ramesh Narayan , Insu Yi

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

We analyze the configuration of a thin rotating accretion disk, which is embedded in a magnetic field inducing a backreaction in the gravitating plasma. The aim of this study is to determine the conditions under which the gaseous accretion…

Solar and Stellar Astrophysics · Physics 2015-06-05 Giovanni Montani , Nakia Carlevaro

We provide a 2.5-dimensional solution to a complete set of viscous hydrodynamical equations describing accretion-induced outflow and then plausible jet around black holes/compact objects. We prescribe a self-consistent advective…

Astrophysics · Physics 2009-11-13 Shubhrangshu Ghosh , Banibrata Mukhopadhyay

The effects of binary tidal forces on transport within an accretion disk are studied with a time-dependent hydrodynamical model of a two-dimensional isothermal accretion disk. Tidal forces quickly truncate the accretion disk to radii of…

Astrophysics · Physics 2009-10-31 John M. Blondin

The observations and simulations have revealed that large-scale magnetic field and outflows can exist in the inner regions of an advection-dominated accretion disc where the resistive diffusion may also be important. In the present paper,…

High Energy Astrophysical Phenomena · Physics 2020-06-17 S. M. Ghoreyshi

We analyse the stellar distributions on the [Fe/H]-[Mg/Fe] plane for 11 Milky Way-mass galaxies from the FIRE-2 cosmological baryonic zoom-in simulations. Alpha-element bimodality, in the form of two separate sequences on the [Fe/H]-[Mg/Fe]…

Astrophysics of Galaxies · Physics 2025-01-22 Hanna Parul , Jeremy Bailin , Sarah R. Loebman , Andrew Wetzel , Megan Barry , Binod Bhattarai

We analyze the stationary configuration of a thin axisymmetric stellar accretion disk, neglecting non-linear terms in the plasma poloidal velocity components. We set up the Grad-Shafranov equation for the system, including the plasma…

Solar and Stellar Astrophysics · Physics 2021-11-18 Giovanni Montani , Nakia Carlevaro

I present the elements of accretion-disc physics applied to active galactic nuclei. The accretion driving mechanisms are discussed, then models of geometrically-thin discs, both stationary and time-dependent, are addressed. Disc's…

High Energy Astrophysical Phenomena · Physics 2023-03-23 Jean-Pierre Lasota

Slim disks have been received much attention because of the increasing evidence for the super-critical accreting objects. In this paper, we make an attempt to construct a unified model, in which the viscosity and the dimensionless accretion…

Astrophysics · Physics 2009-11-10 Lin-Hong Chen , Jian-Min Wang

As described in the review by Marek Abramowicz (these proceedings), accretion theory is at something of a crossroads. Many theoretical descriptions of observations have centered on the ``hydrodynamic'' approach of the ``standard'' Shakura &…

Astrophysics · Physics 2007-05-23 Michael A. Nowak

We show that viscous, transonic accretion disks which start with sub-Keplerian angular momentum at the outer boundary reproduce the features of the so-called thick, thin, slim and other accretion disk models depending upon the accretion…

Astrophysics · Physics 2007-05-23 Sandip K. Chakrabarti

The effects of radial advection and thermal diffusion were considered in investigating the linear stability of an optically thin, two-temperature accretion disc. If the disc has only very little advection, we proved that the thermal…

Astrophysics · Physics 2015-06-24 Xue-Bing Wu

We study ejection mechanisms for two kinds of steady jets: one observed from black hole binaries in the low/hard state and the other from SS433. The specific energy of the ejected gas is required to be positive for the jets to get to…

High Energy Astrophysical Phenomena · Physics 2022-10-21 Hajime Inoue

We study the evolution of viscous, isothermal, rotating, thin, axisymmetric accretion disks around a compact object using Smoothed Particle Hydrodynamics. We emphasize the effects of different choices of viscosity prescriptions on the…

Astrophysics · Physics 2008-02-03 Sandip K. Chakrabarti , Diego Molteni

Hot, tenuous advection-dominated accretion flows around black holes are ideal sites for the Fermi acceleration of relativistic particles at standing shock waves in the accretion disc. Previous work has demonstrated that the…

High Energy Astrophysical Phenomena · Physics 2020-02-17 Jason P. Lee , Peter A. Becker