Hard X-ray emitting black hole fed by accretion of low angular momentum matter

Details Hard X-ray emitting black hole fed by accretion of low angular momentum matter Hard X-ray emitting black hole fed by accretion of low angular momentum matter

1999-02-17

arxiv.org/abs/astro-ph/9902243v1

Astronomy and Astrophysics

Astrophysics

15 pages, 2 figures, submitted to ApJ Lett

Scientific paper

10.1086/312016

Observed spectra of Active Galactic Nuclei (AGN) and luminous X-ray binaries in our Galaxy suggest that both hot (~10^9 K) and cold (~10^6 K) plasma components exist close to the central accreting black hole. Hard X-ray component of the spectra is usually explained by Compton upscattering of optical/UV photons from optically thick cold plasma by hot electrons. Observations also indicate that some of these objects are quite efficient in converting gravitational energy of accretion matter into radiation. Existing theoretical models have difficulties in explaining the two plasma components and high intensity of hard X-rays. Most of the models assume that the hot component emerges from the cold one due to some kind of instability, but no one offers a satisfactory physical explanation for this. Here we propose a solution to these difficulties that reverses what was imagined previously: in our model the hot component forms first and afterward it cools down to form the cold component. In our model, accretion flow has initially a small angular momentum, and thus it has a quasi-spherical geometry at large radii. Close to the black hole, the accreting matter is heated up in shocks that form due to the action of the centrifugal force. The hot post-shock matter is very efficiently cooled down by Comptonization of low energy photons and condensates into a thin and cold accretion disk. The thin disk emits the low energy photons which cool the hot component.

Affiliated with

Also associated with

No associations

Rating

Hard X-ray emitting black hole fed by accretion of low angular momentum matter does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Hard X-ray emitting black hole fed by accretion of low angular momentum matter, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hard X-ray emitting black hole fed by accretion of low angular momentum matter will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-178197