BINARY ACTIVE GALACTIC NUCLEI IN STRIPE 82: CONSTRAINTS ON SYNCHRONIZED BLACK HOLE ACCRETION IN MAJOR MERGERS

AbstractSeveral works have shown that there is an empirical correlation between the star formation rate and the luminosity of the active galactic nucleus (and thus the black hole accretion rate, ṀBH) of Seyfert galaxies. This suggests a physical relation between the gas forming stars on kpc scales and the gas on sub-pc scales that is feeding the black hole. Simulations predict this relation and also that the correlation should be more prominent on smaller physical scales. We have compiled high angular resolution (0.4–0.8″) mid-infrared spectroscopy obtained with T-ReCS, VISIR, and Michelle of 29 Seyferts. We use the 11.3 μm PAH feature to probe the star formation activity in the inner ~65 pc, and its relation with the ṀBH on these physical scales.

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The cosmic history of the X–ray background

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2004.1517 ◽

2005 ◽

Vol 363 (1828) ◽

pp. 685-694 ◽

Cited By ~ 1

Author(s):

Amy J. Barger

Keyword(s):

Black Hole ◽

Galactic Nuclei ◽

X Ray ◽

Supermassive Black Hole ◽

Black Hole Accretion ◽

History Of ◽

Dominant Period ◽

X Ray Background ◽

Hole Accretion ◽

Cosmic History

The Chandra and XMM–Newton X–ray observatories have detected obscured active galactic nuclei (AGN) and almost fully resolved the X–ray background into discrete sources. Ground–based observations of the X–ray sources enable the reconstruction of the history of supermassive black hole accretion from the earliest times to the present. A dramatic cosmic downsizing of AGN luminosities is seen at recent times. Correspondingly, the production rate of the AGN radiation drops rapidly, and the dominant period of supermassive black hole production is seen to be at redshifts near z = 1.

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BEYOND THE STANDARD MODEL OF THE DISC–LINE SPECTRAL PROFILES FROM BLACK HOLE ACCRETION DISCS

Acta Polytechnica ◽

10.14311/ap.2014.54.0301 ◽

2014 ◽

Vol 54 (4) ◽

pp. 300-304

Author(s):

Vjaceslav Sochora ◽

Vladimír Karas ◽

Jirí Svoboda ◽

Michal Dovciak

Keyword(s):

Black Hole ◽

Gravitational Field ◽

Spectral Line ◽

Galactic Nuclei ◽

Accretion Disc ◽

Beyond The Standard Model ◽

Black Hole Accretion ◽

The Standard Model ◽

Spectral Profiles ◽

Hole Accretion

The strong gravitational field of a black hole has distinct effects on the observed profile of a spectral line from an accretion disc near a black hole. The observed profile of the spectral line is broadened and skewed by a fast orbital motion and redshifted by a gravitational field. These effects can help us to constrain the parameters of a system with a black hole, both in active galactic nuclei and in a stellar-mass black hole. Here we explore the fact that an accretion disc emission can be mathematically imagined as a superposition of radiating accretion rings that extend from the inner edge to the outer rim of the disc, with some radially varying emissivity. In our work, we show that a characteristic double-horn profile of several radially confined (relatively narrow) accretion rings or belts could be recognized by the planned instruments onboard future satellites (such as the proposed ESA Large Observatory for X-ray Timing).

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