English
Related papers

Related papers: Observational hints on the torus obscuring gas beh…

200 papers

Observations of the Seyfert 2 and starburst galaxy NGC 7130 with the Chandra X-ray Observatory illustrate that both of these phenomena contribute significantly to the galaxy's detectable X-ray emission. The active galactic nucleus (AGN) is…

Astrophysics · Physics 2014-10-13 N. A. Levenson , K. A. Weaver , T. M. Heckman , H. Awaki , Y. Terashima

The X-ray spectra of active galactic nuclei (AGN) unveil properties of matter around the super massive black hole (SMBH). We investigate the X-ray spectra of AGN focusing on Compton reflection and fluorescence, important processes of…

Astrophysics of Galaxies · Physics 2014-08-12 S. Falocco , F. J. Carrera , X. Barcons , G. Miniutti , A. Corral

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 present the measurement of the line-of-sight extinction of the dusty torus for a large number of obscured active galactic nuclei (AGNs) based on the reddening of the colour of the variable flux component in near-infrared (NIR)…

We report the broadband X-ray spectra of the ultra-luminous infrared galaxy (ULIRG) UGC 5101 in the 0.25-100 keV band observed with Swift/Burst Alert Telescope (BAT), NuSTAR, Suzaku, XMM-Newton, and Chandra. A Compton-thick AGN obscured…

Astrophysics of Galaxies · Physics 2017-02-08 Saeko Oda , Atsushi Tanimoto , Yoshihiro Ueda , Masatoshi Imanishi , Yuichi Terashima , Claudio Ricci

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

The fraction of AGN with photoelectric absorption in the X-rays ranging from NH of 10^{22} up to about 10^{24} cm^{-2} (Compton-thin) appears observationally to be anticorrelated to their luminosity Lx. This recently found evidence is used…

Astrophysics · Physics 2009-11-11 Alessandra Lamastra , G. Cesare Perola , Giorgio Matt

The Two Micron All Sky Survey (2MASS) is finding previously unidentified, luminous red active galactic nuclei (AGN). This new sample has a space density similar to, or greater than, previously known AGN, suggesting that a large fraction of…

We present a structural study of 182 obscured Active Galactic Nuclei (AGNs) at z<=1.5, selected in the COSMOS field from their extreme infrared to X-ray luminosity ratio and their negligible emission at optical wavelengths. We fit optical…

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

We present the results of a joint {\it XMM-Newton} and {\it NuSTAR} campaign on the active galactic nucleus (AGN) IC 4329A, consisting of 9 $\times$ 20 ks {\it XMM-Newton} observations, and 5 $\times$ 20 ks {\it NuSTAR} observations within…

We present the analysis of multiepoch observations of a set of 12 variable, Compton-thin, local (z<0.1) active galactic nuclei (AGN) selected from the 100-month BAT catalog. We analyze all available X-ray data from \chandra, \xmm, and…

Astrophysics of Galaxies · Physics 2023-10-18 N. Torres-Albà , S. Marchesi , X. Zhao , I. Cox , A. Pizzetti , M. Ajello , R. Silver

We perform X-ray spectral analyses to derive characteristics (e.g., column density, X-ray luminosity) of $\approx$10,200 active galactic nuclei (AGNs) in the XMM-Spitzer Extragalactic Representative Volume Survey (XMM-SERVS), which was…

We present numerical simulations of properties of a parsec-scale torus exposed to illumination by the central black hole in an active galaxy (AGN). Our physical model allows to investigate the balance between the formation of winds and…

Astrophysics of Galaxies · Physics 2016-03-23 Anton Dorodnitsyn , Tim Kallman , Daniel Proga

We present X-ray observations of the ultraluminous infrared galaxy, UGC 5101, thought to contain a buried active galactic nucleus (AGN) based on observations in other wavebands. We detected an absorbed hard component at >3 keV, as well as…

Astrophysics · Physics 2009-11-10 Masatoshi Imanishi , Yuichi Terashima , Naohisa Anabuki , Takao Nakagawa

The inner structure of AGNs is expected to change below a certain luminosity limit. The big blue bump, footprint of the accretion disk, is absent for the majority of low-luminosity AGNs (LLAGNs). Moreover, recent simulations suggest that…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 J. A. Fernández-Ontiveros , M. A. Prieto , J. A. Acosta-Pulido , M. Montes

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 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 nuclear obscurer of Active Galactic Nuclei (AGN) is poorly understood in terms of its origin, geometry and dynamics. We investigate whether physically motivated geometries emerging from hydro-radiative simulations can be differentiated…

High Energy Astrophysical Phenomena · Physics 2021-07-14 Johannes Buchner , Murray Brightman , Mislav Baloković , Keiichi Wada , Franz E. Bauer , Kirpal Nandra

We present calculations of AGN winds at ~parsec scales, along with the associated obscuration. We take into account the pressure of infrared radiation on dust grains and the interaction of X-rays from a central black hole with hot and cold…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Anton Dorodnitsyn , Timothy Kallman