Questions tagged [accretion-disk]
An accretion disk is the disk around a compact star that accumulates matter from e.g. a companion star by the Roche lobe overflow or stellar wind transfer.
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Are there black holes without accretion disk but emitting astrophysical jets?
First a citation from Wikipedia page about relativistic jets:
"Jets may also be observed from spinning neutron stars. An example is pulsar IGR J11014-6103, which has the largest jet so far ...
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Why does the jet come out perpendicular to the accretion disc?
Why does the jet always come out perpendicular to the plane of the accretion disc around a black hole?
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Is the Accretion Disk of a Black Hole just an illusion?
As a matter of fact, I recently learnt that as an object is approaching a black hole, to an outside observer the object seems to be getting slower and slower and will cross the event horizon after an ...
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I have a couple of questions regarding the physics of planet Miller and the black hole it's orbiting from the movie "Interstellar" [closed]
I watched the movie and thoroughly enjoyed it. I had a couple of questions regarding the physics, so I looked for answers. I got them, but I was left even more questions.
I know that a lot of these ...
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Some doubts regarding the Paczynsky-Wiita potential for modeling accretion disk around Schwarzschild black holes?
I am presently studying accretion processes around Schwarzschild black holes and for this purpose I am reading the classic paper by Paczynsky and Wiita (1980). In this paper, the authors define the ...
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Is an exact description of accretion flow possible very close to a Schwarzschild black hole?
While modelling accretion disks around Schwarzschild black holes, various pseudo-Newtonian potentials are prescribed and then compared to general relativistic results. Though the pseudo-Newtonian ...
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Physical importance of centrifugal force and Coriolis force in the context of the restricted 3-body problem
In the textbook Galactic Dynamics (Binney and Tremaine), the restricted three-body problem to find the trajectory of a test mass that orbits in the combined gravitational field of two masses $M$ and $...
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What happens to the accretion disk when two black holes merge?
I'm aware that accretion disks around black holes are formed from the swirling mass of matter that is slowly being stripped of its atoms, but what happens to it when two black holes merge? I was ...
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AGN accretion disk double peak explained?
I have a question to the following lecture: https://ned.ipac.caltech.edu/level5/Fabian4/Fab2_2.html
In Figure 3 it says that a narrow annuli of a Newtonian disk should alrdy show a double peak ...
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Effective potential for Kerr geometry
In the review Foundations of Black Hole Accretion Disk Theory, the authors defines an effective potential for Kerr geometry as (Chap. 2, eqn. 23)
$$\mathcal{U}_{eff}=-\frac{1}{2}\ln\left|g^{tt}-2lg^{t\...
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Newtonian/Relativistic Solutions of Fluid Disks in orbit around a massive body
I have been trying to make an RMHD (Relativistic Magneto-Hydro Dynamics) Set-up of a Disk around a Massive Rotational Body.
The initial paper I have been studing a paper which uses a Fishbone & ...
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Physical significance of angular velocity of orbits around Kerr black holes
For the Kerr metric $$ds^2=\left(g_{tt}-\frac{g_{t\phi}^2}{g_{\phi\phi}}\right)dt^2+g_{\phi\phi}\left(d\phi-\omega dt\right)^2+g_{rr}dr^2+g_{\theta\theta}d\theta^2$$ the angular momentum is defined as ...
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What are Quasi-Periodic Oscilations and how can they be used to determine the mass of black holes?
Quasi-Periodic Oscillations (QPOs) are observed in almost all accreting systems and they provide an essential tool to explore accretion flows from compact objects.
But I couldn't understand what ...
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Four-momentum of a photon emitted from an accretion disk
Consider a non-rotating compact object surrounded by a revolving accretion disk. A distant observer sees the disk in an edge-on position. The center of the disk may be taken as the origin of $r-\theta-...
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How can a gas be in circular orbit when centrifugal force is dominant in an accretion disk around a black hole?
In the textbook "Black Holes, White Dwarfs and Neutron Stars: The Physics of Compact Objects" by Shapiro and Teukolsky, the author makes the following statement while discussing the standard thin disk ...
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