X-ray absorption in INTEGRAL AGN: Host galaxy inclination

Abstract

In this work the INTEGRAL hard X-ray selected sample of AGN has been used to investigate the possible contribution of absorbing material distributed within the host galaxies to the total amount of NH measured in the X-ray band. We collected all the available axial ratio measurements of the galaxies hosting our AGN together with their morphological information and find that also for our hard X-ray selected sample a deficit of edge-on galaxies hosting type 1 AGN is present. We estimate that in our hard X-ray selected sample there is a deficit of 24% (+/- 5%) of type 1 AGN. Possible bias in redshift has been excluded, as we found the same effect in a well determined range of z where the number and the distributions of the two classes are statistically the same. Our findings clearly indicate that material located in the host galaxy on scales of hundreds of parsecs and not aligned with the putative absorbing torus of the AGN can contribute to the total amount of column density. This galactic absorber can be large enough to hide the broad line region of some type 1 AGN causing their classification as type 2 objects and giving rise to the deficiency of type 1 in edge-on galaxies.

19 pages, accepted for publication in A&A

References in corpus (16)

• The Co-Evolution of Galaxies and Supermassive Black Holes: Insights from Surveys of the Contemporary Universe
• HyperLEDA. III. The catalogue of extragalactic distances
• BAT AGN Spectroscopic Survey - V. X-ray properties of the Swift/BAT 70-month AGN catalog
• Molecular line emission in NGC1068 imaged with ALMA. I An AGN-driven outflow in the dense molecular gas
• Merging and Clustering of the Swift BAT AGN Sample
• The Toroidal Obscuration of Active Galactic Nuclei
• X-ray nature of the LINER nuclear sources
• Hubble Space Telescope Near-Infrared Snapshot Survey of 3CR radio source counterparts at low redshift
• Swift-XRT observation of 34 new INTEGRAL/IBIS AGNs: discovery of Compton thick and other peculiar sources
• The central parsecs of active galactic nuclei: challenges to the torus
• HST unveils a compact mildly relativistic Broad Line Region in the candidate true type 2 NGC 3147
• Shedding Light on the Compton-thick Active Galactic Nucleus in the Ultra-luminous Infrared Galaxy UGC 5101 with Broadband X-ray Spectroscopy
• A mid-infrared statistical investigation of clumpy torus model predictions
• Detection of faint broad emission lines in type 2 AGN: I. Near infrared observations and spectral fitting
• Where are Compton-thick radio galaxies? A hard X-ray view of three candidates
• Heating and cooling of the neutral ISM in the NGC4736 circumnuclear ring

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• The relation between AGN type and host galaxy properties
• The role of AGN and its obscuration on the position of the host galaxy relative to Main Sequence
• A Hubble Space Telescope Imaging Survey of Low-Redshift Swift-BAT Active Galaxies
• Reconciling X-ray and 21cm HI absorption gas column densities toward obscured AGN