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Дата изменения: Unknown Дата индексирования: Sun Apr 10 04:20:17 2016 Кодировка: Поисковые слова: ультрафиолетовое излучение |
Evidences of supercritical accretion onto black hole in SS433 |
Russian version |
SS433 is a close binary system, one star is a supergiant, a second one is a
black hole. The supergiant's matter overflows to the neighbouring black
hole and floods the hole with a powerful mass flux: 6 millions of billions
tons per second (that is one Earth mass for 11 days). Even a black hole
cannot accept such an enormous mass flux, a supercritical accretion disk
appears, all the excess gas glows up to several tens of thousands degrees
and is ejected off the disk with enormous velocities. On the disk axes a
huge crater (funnel) is formed composed of the outflowing gas. Astrophycists
of the World know that supercritical disks do exist, however, there are
no direct arguments to proof that phenomenon: the black hole is perfectly
covered by the gas. A gas fountain from a black hole is the
only indication of the supercritical accretion.
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Fig.1.
An expected power spectrum (scheme) of the supercritical accretion disk.
The flat region between frequencies f_1 and f_2 is an evidence that in
this place the disk becomes thick (spherization radius of the disk).
At the spherization radius all signals of the accretion disk are
independend ("white noise"). From left side of f_1, at lower frequencies,
the disk is still thin (standard disk). From left side of f_2, at higher
frequancies, the variability is smoothed by the funnel.
Fig.2.
The observed power spectra of X-ray emission at different orientations of
the accretion disk and the funnel: the maximal opening of the disk to
the observer (red) and the edge-on disk (blue). When the disk is open to
the observer (red) we can see the funnel, here we have detected the flat
region. When the disk and the funnel are totally blocked (blue) we see
only the reflected radiation off the clouds far away from the disk.
The frequency in Hertz (0.001 Hz corresponds to 1000-second period).
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