The Unified Model of Active Galactic Nuclei. II. Evolutionary Connection
نویسندگان
چکیده
منابع مشابه
The Unified Model of Active Galactic Nuclei: Ii. Evolutionary Connection
The classical unified model is challenged by the presence of various kinds of Seyfert 2 galaxies. We assemble a sample composed of 243 nearby Seyfert galaxies with redshifts z ≤ 0.05 to test the unification scheme. The sample contains 94 broad line Seyfert 1s (BLS1s), 44 narrow line Seyfert 1s (NLS1s), 36 X-ray absorbed hidden broad line region (BLR) Seyfert 2s (HBLR S2s), 42 X-ray absorbed non...
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The properties of the absorption in type 2, narrow line AGNs are reviewed by focusing on the X-ray indicators. I discuss the properties of the cold absorbing medium (the putative torus) and of the reprocessed components, as well as their implications for the unified model. The relation between optical classification and X-ray absorption is examined. The case of “fossil” AGNs, whose type 2 class...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2007
ISSN: 0004-637X,1538-4357
DOI: 10.1086/513685