Constraining Torus Models for AGNs Using X-Ray Observations

Abstract

In Unification Models, Active Galactic Nuclei (AGN) are believed to be surrounded by an axisymmetric structure of dust and gas, which greatly influences their observed properties according to the direction from which they are observed. The main aim of this work is to constrain the properties of this obscuring material using X-Ray observations. The distribution of column densities observed by Chandra in the Chandra Deep Field South is used to determine geometrical constraints for already proposed torus models. It is found that the best torus model is given by a classical `donut shape' with an exponential angular dependency of the density profile. The opening angle is strongly constrained by the observed column densities. Other proposed torus models are clearly rejected by the X-Ray observations.

10 pages, 4 figures, submitted to A&A

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• Smooth and Clumpy Dust Distribution in AGN: a Direct Comparison of two Commonly Explored Infrared Emission Models
• A large population of mid-infrared selected, obscured active galaxies in the Bootes field
• Near-Infrared Reverberation by Dusty Clumpy Tori in Active Galactic Nuclei
• Fitting LINER nuclei within the AGN family: A matter of obscuration?
• Exploring AGN and Star Formation Activity of Massive Galaxies at Cosmic Noon
• Jet and Torus Orientations in High Redshift Radio Galaxies
• Radio stacking reveals evidence for star formation in the host galaxies of X-ray selected active galactic nuclei at z<1
• Apparent quasar disc sizes in the "bird's nest" paradigm