Evolution of broad-line emission from active galactic nuclei

  title={Evolution of broad-line emission from active galactic nuclei},
  author={Moshe Elitzur and Luis C. Ho and Jonathan R. Trump},
  journal={Monthly Notices of the Royal Astronomical Society},
Apart from viewing-dependent obscuration, intrinsic broad-line emission from active galactic nuclei (AGN) follows an evolutionary sequence: type 1 → 1.2/1.5 → 1.8/1.9 → 2a s the accretion rate on to the central black hole is decreasing. This spectral evolution is controlled, at least in part, by the parameter Lbol/M 2/3 , where Lbol is the AGN bolometric luminosity and M is the black hole mass. Both this dependence and the double-peaked profiles that emerge along the sequence arise naturally in… 

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