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Related papers: High precision X-ray logN-logS distributions: impl…

200 papers

We present the timing analysis of the four archived XMM-Newton observations of PG 1211+143. The source is well-known for its spectral complexity, comprising a strong soft-excess and different absorption systems. Soft energy band (0.3-0.7…

High Energy Astrophysical Phenomena · Physics 2015-05-30 B. De Marco , G. Ponti , P. Uttley , M. Cappi , M. Dadina , A. C. Fabian , G. Miniutti

We present a study of optically selected dual AGN with projected separations of 3--97~kpc. Using multi-wavelength (MWL) information (optical, X-rays, mid-IR), we characterized the intrinsic nuclear properties of this sample and compared…

We report a new sample of obscured active galactic nuclei (AGNs) selected from the XMM serendipitous source and AKARI point-source catalogs. We match X-ray sources with infrared (18 and 90 micron) sources located at |b|>10 deg to create a…

Astrophysics of Galaxies · Physics 2015-11-18 Yuichi Terashima , Yoshitaka Hirata , Hisamitsu Awaki , Shinki Oyabu , Poshak Gandhi , Yoshiki Toba , Hideo Matsuhara

We present the observed-frame optical, near- and mid-infrared properties of X-ray selected AGN in the Lockman Hole. Using a likelihood ratio method on optical, near-infrared or mid-infrared catalogues, we assigned counterparts to 401 out of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 E. Rovilos , S. Fotopoulou , M. Salvato , V. Burwitz , E. Egami , G. Hasinger , G. Szokoly

Hard X-ray ($\geq 10$ keV) observations of Active Galactic Nuclei (AGN) can shed light on some of the most obscured episodes of accretion onto supermassive black holes. The 70-month Swift/BAT all-sky survey, which probes the 14-195 keV…

We present a multi-waveband analysis of a 126 galaxy sub-sample of the 12 micron galaxy sample (12MGS), for which we have carried out a detailed X-ray spectral analysis of in a previous paper. We present optical activity classes and we…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Murray Brightman , Kirpal Nandra

Variability at all observed wavelengths is a distinctive property of AGN. Hard X-rays provide us with a view of the innermost regions of AGN, mostly unbiased by absorption along the line of sight. Swift/BAT offers the unique opportunity to…

High Energy Astrophysical Phenomena · Physics 2015-06-17 S. Soldi , V. Beckmann , W. H. Baumgartner , G. Ponti , C. R. Shrader , P. Lubinski , H. A. Krimm , F. Mattana , J. Tueller

With the superb angular resolution of the Chandra Observatory, it is now possible to detect X-ray point sources, either embedded in galaxy clusters or along the cluster line of sight, which could not be resolved by previous instruments.…

Astrophysics · Physics 2009-11-11 M. Branchesi , I. M. Gioia , C. Fanti , R. Fanti , N. Cappelluti

We study the properties of a sample of 211 heavily-obscured Active Galactic Nucleus (AGN) candidates in the Extended Chandra Deep Field-South selecting objects with f_24/f_R>1000 and R-K>4.5. Of these, 18 were detected in X-rays and found…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 E. Treister , C. Cardamone , K. Schawinski , C. M. Urry , E. Gawiser , S. Virani , P. Lira , J. Kartaltepe , M Damen , E. N. Taylor , E. Le Floc'h , Stephen Justham , A. Koekemoer

We have obtained three epochs of Chandra ACIS-I observations (totaling $\sim$184 ks) of the nearby spiral galaxy NGC~300 to study the logN-logS distributions of its X-ray point source population down to $\sim$2$\times$10$^{-15}$ erg…

High Energy Astrophysical Phenomena · Physics 2017-01-18 Breanna Binder , Jacob Gross , Benjamin F. Williams , Michael Eracleous , Terrance J. Gaetz , Paul P. Plucinsky , Evan D. Skillman

We use Herschel-PACS far-infrared data, combined with previous multi-band information and mid-IR spectra, to properly account for the presence of an active nucleus and constrain its energetic contribution in luminous infrared (IR) sources…

We adopt a Bayesian X-ray spectral approach to investigate the accretion properties of unobscured ($20<\log(N_{\rm H}/{\rm cm}^{-2}<22$) and obscured ($22< \log(N_{\rm H}/{\rm cm}^{-2}<24$) active galactic nuclei (AGN) to shed light on the…

We provide constraints on the AGN contribution to the mid-IR extragalactic background light from a correlation analysis of deep X-ray and mid-IR observations in two regions centred on the Lockman Hole (LH) and Hubble Deep Field North…

We present an X-ray spectral analysis of 126 galaxies of the 12 micron galaxy sample. We pay particular attention to Compton thick AGN with the help of new spectral fitting models that we have produced, which are based on Monte-Carlo…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Murray Brightman , Kirpal Nandra

The ROSAT Deep Survey in the Lockman Hole contains a complete sample of 50 X-ray sources with fluxes in the 0.5-2.0 keV band larger than 5.5E-15 erg/cm2/s. Previous work has provided optical identification of 46 of the 50 X-ray sources;…

We report on the results of the first XMM systematic "excess variance" study of all the radio quiet, X-ray un-obscured AGN. The entire sample consist of 161 sources observed by XMM for more than 10 ks in pointed observations which is the…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Gabriele Ponti , Iossif Papadakis , Stefano Bianchi , Matteo Guainazzi , Giorgio Matt , Phil Uttley , Fonseca Bonilla , Nuria

AIMS: We investigate here the nature of all the sources (35 in total) in the XBS survey (which is 86% optically identified) showing an optical spectrum dominated by the light from the host galaxy with no evidence (or little evidence) for…

Astrophysics · Physics 2009-11-13 A. Caccianiga , P. Severgnini , R. Della Ceca , T. Maccacaro , F. J. Carrera , M. J. Page

Aims: Active Galactic Nuclei are known to be variable throughout the electromagnetic spectrum. An energy domain poorly studied in this respect is the hard X-ray range above 20 keV. Methods: The first 9 months of the Swift/BAT all-sky survey…

A large population of heavily obscured, Compton Thick AGNs is predicted by models of galaxy formation, models of Cosmic X-ray Background and by the ``relic'' super-massive black-hole mass function measured from local bulges. However, so far…