QUASI-PERIODIC OSCILLATIONS AND FREQUENCIES IN AN ACCRETION DISK AND COMPARISON WITH THE NUMERICAL RESULTS FROM NON-ROTATING BLACK HOLE COMPUTED BY THE GRH CODE

The shocked wave created on the accretion disk after different physical phenomena (accretion flows with pressure gradients, star-disk interaction etc.) may be responsible observed Quasi Periodic Oscillations (QPOs) in X-ray binaries. We present the set of characteristics frequencies associated with accretion disk around the rotating and non-rotating black holes for one particle case. These persistent frequencies are results of the rotating pattern in an accretion disk. We compare the frequency's from two different numerical results for fluid flow around the non-rotating black hole with one particle case. The numerical results are taken from Refs. 1 and 2 using fully general relativistic hydrodynamical code with non-selfgravitating disk. While the first numerical result has a relativistic tori around the black hole, the second one includes one-armed spiral shock wave produced from star-disk interaction. Some physical modes presented in the QPOs can be excited in numerical simulation of relativistic tori and spiral waves on the accretion disk. The results of these different dynamical structures on the accretion disk responsible for QPOs are discussed in detail.

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THE EFFECTS OF DIFFERENT PERTURBATIONS ON THE DYNAMICS OF THE ACCRETION DISK AROUND THE BLACK HOLE

International Journal of Modern Physics A ◽

10.1142/s0217751x07036166 ◽

2007 ◽

Vol 22 (10) ◽

pp. 1875-1898 ◽

Cited By ~ 1

Author(s):

ORHAN DÖNMEZ

Keyword(s):

Shock Wave ◽

Black Hole ◽

Shock Waves ◽

Accretion Disk ◽

Periodic Oscillation ◽

Single Star ◽

Special Cases ◽

Galactic Black Hole ◽

General Relativistic ◽

Armed Spiral

We investigate the special cases of the formation of shocks in the accretion disks around the nonrotating (Schwarzschild) black holes in cases where one or few stars perturb the disk. We model the structure of disk with a 2D fully general relativistic hydrodynamic code and investigate a variety of cases in which the stars interacting with the disk are captured at various locations. We have found the following results: (1) if the stars perturb the disk at nonsymmetric locations, a moving one-armed spiral shock wave is produced and it destroys the disk eventually; (2) if the disk is perturbed by a single star located close to the black hole, a standing shock wave is produced while the disk becomes an accretion tori; (3) if the disk is perturbed by stars at symmetric locations, moving two-armed spiral shock waves are produced while the disk reaches a steady state; (4) continuous injection of matter into the stable disk produces a standing shock wave behind the black hole. Our outcomes reinforce the view that different perturbations on the stable accretion disk carry out different types of shock waves which produce Quasi-Periodic Oscillation (QPO) phenomena in galactic black hole candidates and it is observed as a X-ray.

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Stochastic Resonance of Accretion Disk and the Persistent Low-Frequency Quasi-Periodic Oscillations in Black Hole X-ray Binaries

Journal of Astrophysics and Astronomy ◽

10.1007/s12036-013-9163-y ◽

2013 ◽

Vol 34 (1) ◽

pp. 33-40 ◽

Cited By ~ 6

Author(s):

Z. Y. Wang ◽

P. J. Chen ◽

D. X. Wang ◽

L. Y. Zhang

Keyword(s):

Black Hole ◽

Stochastic Resonance ◽

Accretion Disk ◽

Low Frequency ◽

Periodic Oscillations ◽

X Ray ◽

X Ray Binaries

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Dynamical Evolution of Accretion Flow onto a Black Hole

Symposium - International Astronomical Union ◽

10.1017/s0074180900116006 ◽

1998 ◽

Vol 188 ◽

pp. 455-456

Author(s):

M. Yokosawa

Keyword(s):

Black Hole ◽

Active Galactic Nuclei ◽

Event Horizon ◽

Accretion Disk ◽

Dynamical Evolution ◽

Galactic Nuclei ◽

Thick Disk ◽

X Ray ◽

General Relativistic ◽

Inner Region

Active galactic nuclei(AGN) produce many type of active phenomena, powerful X-ray emission, UV hump, narrow beam ejection, gamma-ray emission. Energy of these phenomena is thought to be brought out binding energy between a black hole and surrounding matter. What condition around a black hole produces many type of active phenomena? We investigated dynamical evolution of accretion flow onto a black hole by using a general-relativistic, hydrodynamic code which contains a viscosity based on the alpha-model. We find three types of flow's pattern, depending on thickness of accretion disk. In a case of the thin disk with a thickness less than the radius of the event horizon at the vicinity of a marginally stable orbit, the accreting flow through a surface of the marginally stable orbit becomes thinner due to additional cooling caused by a general-relativistic Roche-lobe overflow and horizontal advection of heat. An accretion disk with a middle thickness, 2rh≤h≤ 3rh, divides into two flows: the upper region of the accreting flow expands into the atmosphere of the black hole, and the inner region of the flow becomes thinner, smoothly accreting onto the black hole. The expansion of the flow generates a dynamically violent structure around the event horizon. The kinetic energy of the violent motion becomes equivalent to the thermal energy of the accreting disk. The shock heating due to violent motion produces a thermally driven wind which flows through the atmosphere above the accretion disk. A very thick disk, 4rh≤h,forms a narrow beam whose energy is largely supplied from hot region generated by shock wave. The accretion flowing through the thick disk,h≥ 2rh, cannot only form a single, laminar flow falling into the black hole, but also produces turbulent-like structure above the event horizon. The middle disk may possibly emit the X-ray radiation observed in active galactic nuclei. The thin disk may produce UV hump of Seyfert galaxy. Thick disk may produce a jet observed in radio galaxy. The thickness of the disk is determined by accretion rate, such ashκ κes/cṁf(r) κ 10rhṁf(r), at the inner region of the disk where the radiation pressure dominates over the gas pressure. Here, Ṁ is the accretion rate and ṁ is the normarized one by the critical-mass flux of the Eddington limit. κesandcare the opacity by electron scattering and the velocity of light.f(r) is a function with a value of unity far from the hole.

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Compton Reflection in the Vicinity of a Rotating Black Hole

Symposium - International Astronomical Union ◽

10.1017/s007418090011575x ◽

1998 ◽

Vol 188 ◽

pp. 409-410

Author(s):

A. Maciołek-Niedźwiecki ◽

P. Magdziarz

Keyword(s):

Black Hole ◽

Accretion Disk ◽

Rotating Black Hole ◽

Line Shapes

We study the spectra arising from Compton reflection in the innermost parts of the accretion disk. We emphasize that the so far neglected relativistic distortion of the Compton reflection continuum may strongly affect the derived Fe Kα line shapes.

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SPECTRUM OF THE ACCRETION DISK NEAR THE ROTATING BLACK HOLE

The Ninth Marcel Grossmann Meeting ◽

10.1142/9789812777386_0546 ◽

2002 ◽

pp. 2265-2266

Author(s):

SERGE V. REPIN ◽

ALEXANDER F. ZAKHAROV

Keyword(s):

Black Hole ◽

Accretion Disk ◽

Rotating Black Hole

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General Relativistic Simulations of Early Jet Formation in a Rapidly Rotating Black Hole Magnetosphere

The Astrophysical Journal ◽

10.1086/308986 ◽

2000 ◽

Vol 536 (2) ◽

pp. 668-674 ◽

Cited By ~ 118

Author(s):

Shinji Koide ◽

David L. Meier ◽

Kazunari Shibata ◽

Takahiro Kudoh

Keyword(s):

Black Hole ◽

Jet Formation ◽

Rotating Black Hole ◽

General Relativistic

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General Relativistic Simulation of Jet Formation from Magnetized Accretion Disk

International Astronomical Union Colloquium ◽

10.1017/s0252921100043360 ◽

1997 ◽

Vol 163 ◽

pp. 667-671

Author(s):

Shinji Koide ◽

Kazunari Shibata ◽

Takahiro Kudoh

Keyword(s):

Black Hole ◽

Active Galactic Nuclei ◽

Accretion Disk ◽

Galactic Nuclei ◽

Lorentz Factor ◽

Numerical Code ◽

Jet Formation ◽

Relativistic Jet ◽

Relativistic Regime ◽

General Relativistic

AbstractRecently, superluminal motions are observed not only from active galactic nuclei but also in our Galaxy. These phenomena are explained as relativistic jets propagating almost toward us with Lorentz factor more than 2. For the formation of such a relativistic jet, magnetically driven mechanism around a black hole is most promising. We have extended the 2.5D Newtonian MHD jet model (Shibata & Uchida 1986) to general relativistic regime. For this purpose, we have developed a general relativistic magnetohydrodynamic (GRMHD) numerical code and applied it to the simulation of the magnetized accretion disk around a black hole. We have found the formation of magnetically driven jets with 86 percent of light velocity (i.e. Lorentz factor ~ 2.0).

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