On the Nature of Low-Luminosity Narrow-Line Active Galactic Nuclei

  title={On the Nature of Low-Luminosity Narrow-Line Active Galactic Nuclei},
  author={Ari Laor},
  journal={The Astrophysical Journal},
  • A. Laor
  • Published 26 February 2003
  • Physics
  • The Astrophysical Journal
There is clear observational evidence that some narrow-line (type 2) active galactic nuclei (AGNs) have a hidden broad-line region (BLR) and are thus intrinsically broad-line (type 1) AGNs. Does this AGN unification apply for all type 2 AGNs? Indirect arguments suggest that some "true" type 2 AGNs, i.e., AGNs having no obscured BLR, do exist, but it is not clear why the BLR is missing in these AGNs. Here we point out a possible natural explanation. The observed radius-luminosity relation for… 
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