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Related papers: Fitting LINER nuclei within the AGN family: A matt…

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Most of the optically classified low ionisation narrow emission-line regions (LINERs) nuclei host an active galactic nuclei (AGN). However, how they fit into the unified model (UM) of AGN is still an open question. The aims of this work are…

(abridged)The majority of Active Galactic Nuclei (AGN) suffer from significant obscuration by surrounding dust and gas. X-ray surveys in the 2-10 keV band will miss the most heavily-obscured AGN in which the absorbing column density exceeds…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Stephanie M. LaMassa , Timothy M. Heckman , Andrew A. Ptak , Ann Hornschemeier , Lucimara Martins , Paule Sonnentrucker , Christy Tremonti

We analyze HST spectra and Chandra observations of a sample of 21 LINERs, at least 18 of which genuine AGN. We find a correlation between the X-rays and emission lines luminosities, extending over three orders of magnitude and with a…

Astrophysics of Galaxies · Physics 2015-07-02 Barbara Balmaverde , Alessandro Capetti

Using a suite of X-ray, mid-IR and optical active galactic nuclei (AGN) luminosity indicators, we search for Compton-thick (CT) AGNs with intrinsic L_X>10^42erg/s at z~0.03-0.2, a region of parameter space which is currently poorly…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Andy Goulding , David Alexander , James Mullaney , Jonathan Gelbord , Ryan Hickox , Martin Ward , Mike Watson

We study the incidence of nuclear obscuration on a complete sample of 1310 AGN selected on the basis of their rest-frame 2-10 keV X-ray flux from the XMM-COSMOS survey, in the redshift range 0.3<z<3.5. We classify the AGN as obscured or…

We present archival high resolution X-ray imaging observations of 25 nearby LINERs observed by ACIS on board Chandra. This sample builds on our previously published proprietary and archival X-ray observations, and includes the complete set…

Astrophysics · Physics 2009-11-13 S. Satyapal , R. P. Dudik , B. O'Halloran , M. Gliozzi

We present results from a high resolution X-ray imaging study of nearby LINERs observed by Chandra. This study complements and extends previous X-ray studies of LINERs, focusing on the under-explored population of nearby dust-enshrouded…

Astrophysics · Physics 2009-11-10 R. P. Dudik , S. Satyapal , M. Gliozzi , R. M. Sambruna

We have conducted a comprehensive mid-IR spectroscopic investigation of 67 Low Ionization Nuclear Emission Line Regions (LINERs) using archival observations from the high resolution modules of the Infrared Spectrograph on board the Spitzer…

Astrophysics · Physics 2014-11-18 R. P. Dudik , S. Satyapal , D. Marcu

(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

X-ray variability is very common in active galactic nuclei (AGN), but these variations may not occur similarly in different families of AGN. We aim to disentangle the structure of low ionization nuclear emission line regions (LINERs)…

Astrophysics of Galaxies · Physics 2016-06-15 Lorena Hernandez-Garcia , Josefa Masegosa , Omaira Gonzalez-Martin , Isabel Marquez , Jaime Perea

In this paper we discuss the X-ray properties of 49 local (z<0.035) Seyfert 2 galaxies with HST/WFC2 high-resolution optical coverage. It includes the results of 26 still unpublished Chandra and XMM-Newton observations, which yield 25 (22)…

Astrophysics · Physics 2009-11-11 M. Guainazzi , G. Matt , G. C. Perola

This paper discusses the properties of scattering--dominated active galactic nuclei (AGN). We define these to be AGN for which the direct line-of-sight to the continuum source is obscured by Compton-thick material. The aim is to construct,…

Astrophysics · Physics 2009-10-30 H. Netzer , T. J. Turner , I. M. George

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

We analyse Compton-thick active galactic nuclei (CT AGNs), a heavily obscured subclass that challenges traditional X-ray diagnostics. Using 243 sources from the 70-Month \textit{SWIFT}/BAT catalogue (26 CT, 217 non-CT), we investigate their…

Highly obscured active galactic nuclei (AGN) are common in nearby galaxies, but are difficult to observe beyond the local Universe, where they are expected to significantly contribute to the black hole accretion rate density. Furthermore,…

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

LINERs exist in the nuclei of a large fraction of luminous galaxies, but their connection with the AGN phenomenon has remained elusive. We present Hubble Space Telescope narrowband [O III]5007 and H-alpha+[N II] emission-line images of the…

Astrophysics · Physics 2009-10-31 R. W. Pogge , D. Maoz , L. C. Ho , M. Eracleous

We present a large compilation of reddening estimates from broad-line Balmer decrements for active galactic nuclei (AGNs) with measured X-ray column densities. The median reddening is E(B-V) ~ 0.77 +/- 0.10 for type-1 to type-1.9 AGNs with…

Astrophysics of Galaxies · Physics 2021-12-14 Gunnar W. Jaffarian , C. Martin Gaskell

The analysis of the X-ray data for a sample of 51 LINER nuclei with available X-ray Chandra imaging is reported. Our aim was to investigate the physical mechanisms which power LINER nuclear activity. The use of multiwavelenght information…

Astrophysics · Physics 2007-05-23 I. Marquez , O. Gonzalez-Martin , J. Masegosa , M. A. Guerrero , D. Dultzin-Hacyan

We report the results from an homogeneous analysis of the X-ray (Chandra-ACIS) data available for a sample of 51 LINER galaxies selected from the catalogue by Carrillo et al. (1999) and representative of the population of bright LINER…

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