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Related papers: Accreting Black Holes

200 papers

Cooling flows in galaxy clusters and isolated elliptical galaxies are a source of mass for fueling accretion onto a central supermassive black hole. We calculate the dynamics of accreting matter in the combined gravitational potential of a…

Astrophysics · Physics 2009-10-31 Eliot Quataert , Ramesh Narayan

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

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…

High Energy Astrophysical Phenomena · Physics 2019-06-03 G. S. Bisnovatyi-Kogan

We study accretion environments of active galactic nuclei when a super-massive black hole wanders in a circum-nuclear region and passes through an interstellar medium there. It is expected that a Bondi-Hoyle-Lyttleton type accretion of the…

High Energy Astrophysical Phenomena · Physics 2021-09-03 Hajime Inoue

As the title suggests, the purpose of this chapter is to review the current status of numerical simulations of black hole accretion disks. This chapter focuses exclusively on global simulations of the accretion process within a few tens of…

High Energy Astrophysical Phenomena · Physics 2015-06-15 P. Chris Fragile

We present the results of our studies on accretion disks in the proximity of astrophysical black holes. These disks can be of varying degrees of opacity, geometrical shapes, sizes, and volumes. The central compact object is a Schwarzschild…

High Energy Astrophysical Phenomena · Physics 2023-02-27 Leela Elpida Koutsantoniou

I provide a broad overview of the basic theoretical paradigms of black hole accretion flows. Models that make contact with observations continue to be mostly based on the four decade old alpha stress prescription of Shakura & Sunyaev…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Omer Blaes

Accreting supermassive black hole binaries are powerful multimessenger sources emitting both gravitational and EM radiation. Understanding the accretion dynamics of these systems and predicting their distinctive EM signals is crucial to…

This is an introduction to models of accretion discs around black holes. After a presentation of the non-relativistic equations describing the structure and evolution of geometrically thin accretion discs we discuss their steady-state…

High Energy Astrophysical Phenomena · Physics 2016-08-17 Jean-Pierre Lasota

Tidal effects on clumps of material during random non-stationary accretion onto a black hole produce phenomena with distinct temporal characteristics in observed light-curves. During such non-stationary accretion events, the shape of the…

High Energy Astrophysical Phenomena · Physics 2016-11-15 Uros Kostic , Andrej Cadez , Massimo Calvani , Claudio Germana

In astrophysics, accretion is the process by which a massive object acquires matter. The infall leads to the extraction of gravitational energy. Accretion onto dark compact objects such as black holes, neutron stars, and white dwarfs is a…

General Relativity and Quantum Cosmology · Physics 2024-12-19 Kourosh Nozari , Sara Saghafi , Mohammad Hassani

Modeling the late inspiral and merger of supermassive black holes is central to understanding accretion processes and the conditions under which electromagnetic emission accompanies gravitational waves. We use fully general relativistic,…

General Relativity and Quantum Cosmology · Physics 2015-05-27 Tanja Bode , Tamara Bogdanovic , Roland Haas , James Healy , Pablo Laguna , Deirdre Shoemaker

We study the hydrodynamical evolution of massive accretion disks around black holes, formed when a neutron star is disrupted by a black hole in a binary system. Initial conditions are taken from 3D calculations of coalescing binaries.…

Astrophysics · Physics 2009-11-07 William H. Lee , Enrico Ramirez-Ruiz

Using numerical simulations we study the accretion of a phantom scalar field into a black hole and track the black hole horizon shrinking process. We integrate the amount of field left outside the black hole during the process in terms of…

General Relativity and Quantum Cosmology · Physics 2016-12-16 J. A. González , F. S. Guzmán

Accreting black hole sources show variable outflows at different mass scales. For instance, in the case of galactic nuclei, our own galactic center Sgr A* exhibits flares and outbursts in the X-ray and infrared bands. Recent studies suggest…

High Energy Astrophysical Phenomena · Physics 2024-07-17 Bestin James , Agnieszka Janiuk , Vladimir Karas

The spectrum of the hard X-ray background records the history of accretion processes integrated over the cosmic time. Several observational and theoretical evidences indicate that a significant fraction of the energy density is obscured by…

Astrophysics · Physics 2009-11-10 Andrea Comastri , the Hellas2Xmm team

Motivated by the fact that the universe is dominated by dark matter and dark energy, we consider rotating black holes surrounded by perfect fluid dark matter and study the accretion process in thin disk around such black holes. Here, we are…

General Relativity and Quantum Cosmology · Physics 2023-03-09 Malihe Heydari-Fard , Sara Ghassemi Honarvar , Mohaddese Heydari-Fard

Accreting binaries containing a black hole are stellar systems composed of a normal star and a black hole. Because of the strong gravitational pull of the black hole, matter is removed from the companion star and falls into the compact ob…

Astrophysics · Physics 2008-02-05 Tomaso M. Belloni

We investigate the accretion of test fluids onto regular black holes such as Kehagias-Sfetsos black hole and a regular black hole with Dagum Distribution Function. We analyze the accretion process when different test fluids are falling onto…

General Relativity and Quantum Cosmology · Physics 2017-09-13 Abdul Jawad , M. Umair Shahzad

Plasmas in an accretion flow are heated by MHD turbulence generated through the magneto-rotational instability. The viscous stress driving the accretion is intimately connected to the microscopic processes of turbulence dissipation. We show…

Astrophysics · Physics 2007-07-04 Siming Liu , Christopher L. Fryer , Hui Li