accretion disk

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accretion disk

n.
A disk of interstellar material gathered into orbit by the gravitational field of a celestial object, such as a star or black hole, and gradually spiraling into the object.
Translations
disque d’accrétion
References in periodicals archive ?
The X-ray emission, representing the accretion disc 'feeding' the jet at its base, was captured from Earth orbit by NASA's NuSTAR telescope, while the moment the jet became visible as optical light was caught by the ULTRACAM high-speed camera, mounted on the William Herschel Telescope on La Palma, in the Canary Islands.
This impressive luminosity is caused by intense radiation blasting out from a central engine the accretion disc surrounding a supermassive black hole.
Although it's thought that supermassive black holes can grow indefinitely, there is a theoretical maximum that it will be able to grow by means of the conventional accretion disc method, where gas in close proximity to the supermassive black hole becomes gravitationally attracted, passes the photon sphere and accretes into a disc as the material spirals into the black hole-beyond its event horizon (the boundary beyond which light cannot escape).
The black hole used to be fueled by galactic material such as gas and dust, which fell inward and created a spinning disk of material known as an accretion disc.
Since the material carries substantial angular momentum, it does not settle on the primary immediately, but forms an accretion disc around the white dwarf.
Such baryonic jets, composed by heavy matter, are more likely to be powered by the accretion disc rather than the spin of the black hole.
If a black hole is spinning, it drags space and time with it and that drags the accretion disc, containing the black hole's food, closer towards it.
And after that, after the glow of gases falling into the black hole has faded, what remains would be just the black hole itself, bereft of its incandescent accretion disc.
Together with colleagues, Ingram published a paper in 2009 suggesting that the QPO is driven by this Lense-Thirring effect, when the flat disc of matter surrounding a black hole, known as an accretion disc spirals inwards towards the black hole.
Frank Stefani have shown that the helical MRI very much applies to the Keplerian rotation profile if only the circular magnetic field is produced not entirely from the outside but at least partly from within the accretion disc.
Since eclipse duration gives an indication of the size of the accretion disc, this suggests that the accretion disc was expanding during this time.
Scientists had already suggested that, close to the black hole, the flat accretion disc puffs up into a hot plasma, in which electrons are stripped from their host atoms.