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The obscured quasar population from optical, mid-infrared, and X-ray surveys

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 نشر من قبل Cristian Vignali
 تاريخ النشر 2007
  مجال البحث فيزياء
والبحث باللغة English
 تأليف C. Vignali




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Over the last few years, optical, mid-infrared and X-ray surveys have brought to light a significant number of candidate obscured AGN and, among them, many Type 2 quasars, the long-sought after big cousins of local Seyfert 2 galaxies. However, despite the large amount of multi-wavelength data currently available, a proper census and a panchromatic view of the obscured AGN/quasar population are still missing, mainly due to observational limitations. Here we provide a review of recent results on the identification of obscured AGN, focusing primarily on the population of Type 2 quasars selected in the optical band from the Sloan Digital Sky Survey.



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