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Post Info TOPIC: Markarian 509


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RE: Markarian 509
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Title: Accretion and outflow of gas in Markarian 509
Authors: Jelle Kaastra, Pierre-Olivier Petrucci, Massimo Cappi, Nahum Arav, Ehud Behar, Stefano Bianchi, Graziella Branduardi-Raymont, Elisa Costantini, Jacobo Ebrero, Jerry Kriss, Missagh Mehdipour, Stephane Paltani, Ciro Pinto, Gabriele Ponti, Katrien Steenbrugge, Cor de Vries

A major uncertainty in models for photoionised outflows in AGN is the distance of the gas to the central black hole. We present the results of a massive multiwavelength monitoring campaign on the bright Seyfert 1 galaxy Mrk 509 to constrain the location of the outflow components dominating the soft X-ray band.
Mrk 509 was monitored by XMM-Newton, Integral, Chandra, HST/COS and Swift in 2009. We have studied the response of the photoionised gas to the changes in the ionising flux produced by the central regions. We were able to put tight constraints on the variability of the absorbers from day to year time scales. This allowed us to develop a model for the time-dependent photoionisation in this source.
We find that the more highly ionised gas producing most X-ray line opacity is at least 5 pc away from the core; upper limits to the distance of various absorbing components range between 20 pc up to a few kpc. The more lowly ionised gas producing most UV line opacity is at least 100 pc away from the nucleus.
These results point to an origin of the dominant, slow (v We also determined the chemical composition of the outflow as well as valuable constraints on the different emission regions. We find for instance that the resolved component of the Fe-K line originates from a region 40-1000 gravitational radii from the black hole, and that the soft excess is produced by Comptonisation in a warm (0.2-1 keV), optically thick (tau~10-20) corona near the inner part of the disk.

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ESA spacecraft reveal new anatomy around a black hole
 
A fleet of spacecraft including ESA's XMM-Newton and Integral have shown unprecedented details close to a supermassive black hole. They reveal huge 'bullets' of gas being driven away from the 'gravitational monster'.
The black hole that the team chose to study lies at the heart of the galaxy Markarian 509, 500 million light years away in space. This black hole is colossal, containing 300 million times the mass of the Sun and growing more massive every day as it continues to feed.

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Astronomers reveal new findings from 'monster' black hole

Working as part of an international team, astronomers at the University of Southampton have revealed some striking features in the gases emitted from the regions close to one of the brightest, supermassive black holes known to man.
The results are published in the latest issue of Astronomy and Astrophysics journal.
The team, led by Dr Jelle Kaastra from the SRON Netherlands Institute for Space Research, observed and mapped the environment around this 'monster' black hole, which is in the distant galaxy Markarian 509 and has a mass 300 million times that of the sun.

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Space Telescopes Reveal Secrets of Turbulent Black Hole

An international team of astronomers using five different telescopes has uncovered striking features around a supermassive black hole in the core of the distant galaxy Markarian 509. They found a very hot corona hovering above the black hole and cold gas "bullets" in hotter diffuse gas, speeding outward with velocities over 1 million miles per hour. This corona absorbs and reprocesses the ultraviolet light from the accretion disk encircling the black hole, energizing it and converting it into X-rays. This discovery allows astronomers to make sense of some of the observations of active galaxies that have been hard to explain so far. The heart of the campaign consisted of repeated visible, X-ray, and gamma-ray observations with ESA's XMM-Newton and INTEGRAL satellites, which monitored Markarian 509 for six weeks.
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Title: Suzaku Studies of Wide-Band Spectral Variability of the Bright Type I Seyfert Galaxy Markarian 509
Authors: Hirofumi Noda, Kazuo Makishima, Shin'ya Yamada, Shunsuke Torii, Soki Sakurai, Kazuhiro Nakazawa

The Type I Seyfert galaxy Markarian 509 was observed with Suzaku in 2010 November, for a gross time span of 2.2 days. Timing and spectral properties of the 0.5-45 keV X-rays, detected with the XIS and HXD, consistently revealed the presence of a soft spectral component that remained constant while the total X- ray intensity varied by ±10%. This stable soft component, found in the 0.5-3.0 keV range, was interpreted as a result of thermal Comptonisation in a corona with a temperature of ~ 0.5 keV and an optical depth of ~ 18. The time-avearged 0.5-45 keV Suzaku spectrum was reproduced successfully, as a combination of this thermal Comptonisation component, a harder power-law of photon index ~ 1.8, moderate reflection, and an iron K-emission line. By analysing four archival Suzaku datasets of the same object obtained in 2006, the thermal Comptonisation component, which was stable during the 2.2 day pointing in 2010, was found to vary on time scales of a few weeks, independently of the power-law component. Implications of these results are discussed in terms of the "multi-zone Comptonisation" view, obtained with Suzaku from the black hole binary Cygnus X-1.

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