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Related papers: An Iwasawa-Taniguchi Effect for Compton-thick Acti…

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The majority of Active Galactic Nuclei (AGN) observed by XMM-Newton reveal narrow Fe K-alpha lines at ~ 6.4 keV, due to emission from cold (neutral) material. There is an X-ray Baldwin effect in Type I AGN, in that the equivalent width of…

Astrophysics · Physics 2009-11-10 K. L. Page , P. T. O'Brien , J. N. Reeves , M. J. L. Turner

Recently, Boorman et al. (2018) reported on the discovery of the Iwasawa-Taniguchi (I-T) effect (a.k.a. X-ray Baldwin effect) for Compton-thick AGN. They measured a decrease of the 6.4 keV iron line equivalent width with the 12mu…

Astrophysics of Galaxies · Physics 2018-10-17 Giorgio Matt , Kazushi Iwasawa

The existence of an anti-correlation between the Equivalent Width (EW) of the neutral narrow core of the iron Kalpha emission line and the 2-10 keV luminosity (the so-called `X-ray Baldwin' or `Iwasawa-Taniguchi' effect) has been debated in…

Astrophysics · Physics 2009-11-13 Stefano Bianchi , Matteo Guainazzi , Giorgio Matt , Nuria Fonseca Bonilla

Most Active Galactic Nuclei (AGN) exhibit a narrow Fe Kalpha line at ~ 6.4 keV in the X-ray spectra, due to the fluorescent emission from cold material far from the inner accretion disk. Using XMM-Newton observations, Page et al. found that…

Astrophysics · Physics 2009-11-11 P. Jiang , J. X. Wang , T. G. Wang

We present a selection technique to detect Compton-thick (CT) active galactic nuclei (AGNs) in the 3XMM/SDSS-DR7 cross-correlation. A subsample of 3481 X-ray sources that are detected in the hard band (2-8 keV) and have photometric…

Astrophysics of Galaxies · Physics 2023-09-27 Reham Mostafa , Matteo Guainazzi , Alaa Ibrahim

Using Chandra High Energy Grating (HEG) observations of 32 AGNs, we present a systematic study of the X-ray Baldwin effect (XBE, i.e. the anti-correlation between narrow Fe K{\alpha} line EW and X-ray continuum luminosity for AGN samples)…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Xinwen Shu , Junxian Wang , Tahir Yaqoob , Peng Jiang , Youyuan Zhou

The narrow Fe K$\alpha$ line is one of the main signatures of the reprocessing of X-ray radiation from the material surrounding supermassive black holes, and it has been found to be omnipresent in the X-ray spectra of active galactic nuclei…

Astrophysics of Galaxies · Physics 2015-06-19 Claudio Ricci , Yoshihiro Ueda , Stephane Paltani , Kohei Ichikawa , Poshak Gandhi , Hisamitsu Awaki

In this paper we report on the broadband X-ray properties of a complete sample of 33 absorbed Seyfert galaxies hard X-ray selected with integral. The high quality broadband spectra obtained with both xmm, and integral-IBIS data are well…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-21 A. De Rosa , F. Panessa , L. Bassani , A. Bazzano , A. J. Bird , R. Landi , A. Malizia , M. Molina , P. Ubertini

We report the results obtained by a systematic, broadband (0.5--150 keV) X-ray spectral analysis of moderately obscured (Compton-thin; $22 \leq \log N_{\rm H} < 24$) active galactic nuclei (AGNs) observed with Suzaku and Swift/Burst Alert…

High Energy Astrophysical Phenomena · Physics 2016-08-03 Taiki Kawamuro , Yoshihiro Ueda , Fumie Tazaki , Claudio Ricci , Yuichi Terashima

We confirm that the spectra are best fit by a model containing two Compton reflection components, one from distant material, and the other displaying relativistic broadening, most likely from the inner accretion disk. The degree of…

High Energy Astrophysical Phenomena · Physics 2020-10-07 Linda Baronchelli , Kirpal Nandra , Johannes Buchner

We present a uniform broadband X-ray (0.5-100.0 keV) spectral analysis of 12 Swift/Burst Alert Telescope (BAT) selected Compton-thick ($\log N_{\mathrm{H}}/\mathrm{cm}^{-2} \geq 24$) Active Galactic Nuclei (CTAGNs) observed with Suzaku. The…

High Energy Astrophysical Phenomena · Physics 2018-02-14 Atsushi Tanimoto , Yoshihiro Ueda , Taiki Kawamuro , Claudio Ricci , Hisamitsu Awaki , Yuichi Terashima

[Abridged]We report on the broadband X-ray properties of a complete sample of absorbed Seyfert galaxies hard X-ray selected with INTEGRAL. The sample is composed of 33 sources: 15 are newly discovered above 20 keV while 18 are already known…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 A. De Rosa , F. Panessa , L. Bassani , A. Bazzano , A. Bird , R. Landi , A. Malizia , M. Molina , P. Ubertini

We present here a detailed X-ray spectral analysis of the AGN belonging to the XMM-Newton bright survey (XBS) that comprises more than 300 AGN up to redshift ~ 2.4. We performed an X-ray analysis following two different approaches: by…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 A. Corral , R. Della Ceca , A. Caccianiga , P. Severgnini , H. Brunner , F. J. Carrera , M. J. Page , A. D. Schwope

The narrow component of the iron K$\alpha$ is an almost ubiquitous feature in the X-ray spectra of active galactic nuclei (AGN) and is believed to originate in neutral material, possibly located in the molecular torus. This would imply a…

Heavily obscured accretion is believed to represent an important stage in the growth of supermassive black holes, and to play an important role in shaping the observed spectrum of the Cosmic X-ray Background (CXB). Hard X-ray (E$>$10 keV)…

High Energy Astrophysical Phenomena · Physics 2017-03-29 C. Ricci , Y. Ueda , M. J. Koss , B. Trakhtenbrot , F. E. Bauer , P. Gandhi

We analyze observations obtained with the Chandra X-ray Observatory of bright Compton thick active galactic nuclei (AGNs), those with column densities in excess of 1.5 x 10^{24} cm^{-2} along the lines of sight. We therefore view the…

Astrophysics · Physics 2011-07-21 N. A. Levenson , T. M. Heckman , J. H. Krolik , K. A. Weaver , P. T. Zycki

The X-ray Baldwin effect is the inverse correlation between the equivalent width (EW) of the narrow component of the iron Kalpha line and the X-ray luminosity of active galactic nuclei (AGN). A similar trend has also been observed between…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Claudio Ricci , Stephane Paltani , Yoshihiro Ueda , Hisamitsu Awaki

Recent evidence for a strong 'hard excess' of flux at energies > 20 keV in some Suzaku observations of type 1 Active Galactic Nuclei (AGN) has motivated an exploratory study of the phenomenon in the local type 1 AGN population. We have…

High Energy Astrophysical Phenomena · Physics 2015-06-12 M. M. Tatum , T. J. Turner , L. Miller , J. N. Reeves

In this paper we describe and publicly release a catalogue consisting of 8445 point-like X-ray sources detected in the XMM-XXL north survey. For the 2512 AGN which have reliable spectroscopy, we present the X-ray spectral fitting which has…

This review addresses the current observational status of the Baldwin Effect (BE), an empirical anti-correlation between emission line equivalent width and source luminosity for active galactic nuclei. We provide a brief history of the BE,…

Astrophysics · Physics 2007-05-23 Patrick S. Osmer , Joseph C. Shields
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