On the relation between X-ray absorption and optical extinction in AGN

Date Issued
2016
Author(s)
Ordovás-Pascual, Ignacio
•
Mateos, Silvia
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Carrera, Francisco J.
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Wiersema, Klaas
•
•
•
•
BALLO, Lucia
•
DOI
Abstract
According to the Unified Model of Active Galactic Nuclei (AGN), an X-ray unabsorbed AGN should appear as unobscured in the optical (Type-1) and viceversa (Type-2). However, there is an important fraction (10-30%) of AGN whose optical and X-ray classifications do not match. To provide insight into the origin of such apparent discrepancies, we have conducted two analyses: 1) a detailed study of the UV-to-near-IR emission of two X-ray unabsorbed Type-2 AGN drawn from the Bright Ultra-Hard XMM-Newton Survey (BUXS); 2) a statistical analysis of the optical obscuration and X-ray absorption properties of 159 Type-1 AGN drawn from BUXS to determine the distribution of dust-to-gas ratios in AGN over a broad range of luminosities and redshifts. In our works we have also determined the impact of contamination from the AGN hosts in the optical classification of AGNs. Our studies are already provided very exciting results such as the detection of objects with extreme dust-to-gas ratios, between 300-10000 times below the Galactic dust-to-gas ratio.
Coverage
Active Galactic Nuclei: What's in a Name?
Start page
104
Conferenece
Active Galactic Nuclei: what's in a name?
Conferenece place
Garching
Conferenece date
June 27, 2016 - July 1, 2016
Uri
Url
Ads BibCode
2016agnw.confE.104O
Rights
open.access
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