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Related papers: Compton thick absorber in type 1 quasar 3C 345 rev…

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We present the analysis of a sample of 35 candidate Compton thick (CT-) active galactic nuclei (AGNs) selected in the nearby Universe (average redshift <z>~0.03) with the Swift-BAT 100-month survey. All sources have available NuSTAR data,…

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

The covering factor of Compton-thick obscuring material associated with the torus in active galactic nuclei (AGN) is at present best understood through the fraction of sources exhibiting Compton-thick absorption along the line of sight…

(Abridged) We analyzed the {\it Chandra} and {\it XMM-Newton} archival observations for 72 type 2 quasars at $z<1$. These objects were was selected based on the [O III]$\lambda$5007 optical emission line which we assume to be an approximate…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Jianjun Jia , Andrew Ptak , Timothy Heckman , Nadia Zakamska

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

3C 223 is a radio loud, Type 2 quasar at $z=0.1365$ with an intriguing XMM-Newton spectrum that implicated it as a rare, Compton-thick ($N_{\rm H} \gtrsim 1.25 \times 10^{24}$ cm$^{-2}$) active galactic nucleus (AGN). We obtained…

High Energy Astrophysical Phenomena · Physics 2023-03-01 Stephanie M. LaMassa , Tahir Yaqoob , Panayiotis Tzanavaris , Poshak Gandhi , Timothy Heckman , George Lansbury , Aneta Siemiginowska

Obscured AGN are fundamental to understand the history of Super Massive Black Hole growth and their influence on galaxy formation. However, the Compton-thick AGN (NH>1e24 cm^-2) population is basically unconstrained, with less than few…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 P. Severgnini , A. Caccianiga , R. Della Ceca , V. Braito , C. Vignali , V. La Parola , A. Moretti

Heavily obscured Active Galactic Nuclei (AGN), especially Compton-thick sources with line-of-sight column density ($N_{\rm H,los}$) $>$ 10$^{24}$ cm$^{-2}$, are critical to understanding supermassive black hole (SMBH) growth and the origin…

The obscuration observed in active galactic nuclei (AGN) is mainly caused by dust and gas distributed in a torus-like structure surrounding the supermassive black hole (SMBH). However, properties of the obscuring torus of the AGN in X-ray…

Astrophysics of Galaxies · Physics 2021-06-09 X. Zhao , S. Marchesi , M. Ajello , D. Cole , Z. Hu , R. Silver , N. Torres-Albà

[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 the results of a Suzaku monitoring campaign of the Seyfert 2 galaxy, NGC7582. The source is characterized by very rapid (on timescales even lower than a day) changes of the column density of an inner absorber, together with the…

Astrophysics of Galaxies · Physics 2011-02-11 Stefano Bianchi , Enrico Piconcelli , Marco Chiaberge , Elena Jimenez Bailon , Giorgio Matt , Fabrizio Fiore

The broad band spectra of two Swift/BAT AGNs obtained from Suzaku follow-up observations are studied: NGC 612 and NGC 3081. Fitting with standard models, we find that both sources show similar spectra characterized by a heavy absorption…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Satoshi Eguchi , Yoshihiro Ueda , Hisamitsu Awaki , James Aird , Yuichi Terashima , Richard Mushotzky

We present an exhaustive methodology for fitting Compton-thick X-ray reprocessor models to obscured AGNs and for interpreting the results. We focus on the MYTORUS model but also utilize other models. We apply the techniques to Suzaku,…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Tahir Yaqoob

Here we present the results of a Suzaku observation of the Broad Line Radio Galaxy 3C 445. We confirm the results obtained with the previous X-ray observations which unveiled the presence of several soft X-ray emission lines and an overall…

High Energy Astrophysical Phenomena · Physics 2015-05-27 V. Braito , J. N. Reeves , R. M. Sambruna , J. Gofford

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 discovery of a Compton-thick Active Galactic Nucleus (AGN) at z=4.76 in the 4 Ms Chandra Deep Field South. This object was selected as a V-band dropout in HST/ACS images and previously recognized as an AGN from optical…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 R. Gilli , J. Su , C. Norman , C. Vignali , A. Comastri , P. Tozzi , P. Rosati , M. Stiavelli , W. N. Brandt , Y. Q. Xue , B. Luo , M. Castellano , A. Fontana , F. Fiore , V. Mainieri , A. Ptak

The presence of an obscuring torus at pc-scale distances from the central black hole is the main ingredient for the Unified Model of Active Galactic Nuclei (AGN), as obscured sources are thought to be seen through this structure. However,…

We present the results from an X-ray spectral analysis of active galactic nuclei (AGN) in the Chandra Deep Field-South, AEGIS-XD and Chandra-COSMOS surveys, focussing on the identification and characterisation of the most heavily obscured,…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Murray Brightman , Kirpal Nandra , Mara Salvato , Li-Ting Hsu , Cyprian Rangel

We present the first long \emph{Suzaku} observation of the hyperluminous infrared galaxy IRAS 09104+4109 which is dominated by a Type 2 AGN. The infrared to X-ray SED indicates that the source is an obscured quasar with a Compton-thin…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Chia-Ying Chiang , E. M. Cackett , P. Gandhi , A. C. Fabian

Aims. We present a 0.2--200 keV broad-band study of absorbed AGN observed with INTEGRAL, XMM-Newton, Chandra and ASCA to investigate the continuum shape and the absorbing/reflecting medium properties. Methods. The sources are selected in…

Astrophysics · Physics 2009-11-13 A. De Rosa , L. Bassani , P. Ubertini , F. Panessa , A. Malizia , A. J. Dean , R. Walter
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