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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Disk-like structures spectra vs ring spectra?
In the introduction to this paper (https://arxiv.org/abs/1803.06423) it is mentioned that disk-like spectra was observed in black hole X-ray binaries, when models would expected to be unstable (...
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What causes the heating of a black hole's accretion disk?
Sheperd Doeleman said in a TED video that the accretion disk is heated by friction. Is that correct? I thought it might be adiabatic heating from the compression of the gasses.
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Can Compton scattering increase a photon's energy?
I've read (in Hagai Netzer's book The Physics and Evolution of Active Galactic Nuclei) that "Comptonization in the [black hole's accretion] disk atmosphere can increase the energy of some photons..." [...
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Understanding the notion of lose or win of angular momentum in accretion disk
Here is below a slide of one of my lecture in planetology :
I understand well the fact that ring A will be slow down by friction with ring B since ring B is rotating slower and the inverse process (...
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Wind-fed Accretion and White Dwarf stars
Can a White Dwarf star in a binary system accrete matter via the Wind-fed accretion process?
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Does infalling material leaves a detectable imprint on the black hole's event horizon?
An external observer will never see anything cross the event horizon, and in most explanations the story ends here.
But I wonder what happens with gravitational effects of the material?
For example ...
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Putting the importance of the blackhole image into perspective [closed]
The recent astonishing achievement of obtaining an actual image of a blackhole, resulted from a massive collaborative work using 8 different telescopes and the equally on par efforts in developing the ...
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Why isn't the circumferential light around the M87 black hole's event horizon symmetric?
After the revelation of the first black hole images, it seems there is a bias towards the south side. Is it because of measuring it from earth or is it something more fundamental in the understanding ...
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How can write physics in terms of local rest frame?
Many times I saw that people wrote that we write the equations in terms of local rest frame, for example in the paper of Novikov and Thorne that calculated stress-energy tensor for Kerr blackhole ...
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How to calculate the corotation radius?
I am studying this paper:
P.Ghosh & F.K.Lamb, APJ, 232, pag.259 (1979)
I do not understand how the authors calculate the corotation radius, $r_{co}$, where the matter of the disk has the same ...
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If you fell into a black whole with an accretion disc, but perpendicular
If you fell into a black whole with an accretion disc, but orthogonal to the plane of the disc - would you ever meet the disc?
I'm not asking whether you survive long enough, and obviously we assume ...
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How can a galaxy not be disk shaped [closed]
If a galaxy is the accretion disk for a supermassive black hole, how can it be a shape other than disk?
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Neutron Star LMXB Accretion Spin-Up Estimation
I've been asked to estimate how much mass a neutron star in a low mass X-ray binary would have to accrete in order to be spun up to ~300 Hz. I found the conservation formula
$\frac{d(I\omega)}{dt} = \...
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Why does the accretion disc radiate energy and matter?
Jets of matter and energy are powered by accretion disc i.e., matter spiralling into the massive black hole at the galactic centre. How is this jet formed? I think that the dust particles and gases ...
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Is the average temperature of a big accretion disk colder than a small one?
Suppose we have a Shakura and Sunyaev style accretion disk between $r_1$ and $r_2$. What is the average temperature? We can calculate it by integrating the local temperature $$T(r)=\left [ \frac{3GM\...
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