AGN Obscuration and the Unified Model

作者:Bianchi Stefano*; Maiolino Roberto; Risaliti Guido
来源:Advances in Astronomy, 2012, 782030.
DOI:10.1155/2012/782030

摘要

Unification Models of Active Galactic Nuclei postulate that all the observed differences between type 1 and type 2 objects are due to orientation effects with respect to the line of sight to the observer. The key ingredient of these models is the obscuring medium, historically envisaged as a toroidal structure on a parsec scale. However, many results obtained in the last few years are clearly showing the need for a more complex geometrical distribution of the absorbing media. In this paper, we review the various pieces of evidence for obscuring media on different scales, from the vicinity of the black hole to the host galaxy, in order to picture an updated unification scenario explaining the complex observed phenomenology. We conclude by mentioning some of the open issues.

  • 出版日期2012