Reddening of narrow line regions

  • Adam Wysota
  • C. Martin Gaskell
I. Spectral Studies in the Optical, Ultraviolet and Infrared
Part of the Lecture Notes in Physics book series (LNP, volume 307)


We make a critical comparison of a number of techniques for estimating narrow line region (NLR) reddenings and discuss their accuracy. We confirm that there is a preferred case B′ Hα/Hβ ratio of 3.1 for the NLR. All the reported scatter can be explained by known observational errors and contrary to some earlier claims, there is no evidence for intrinsic spread in the B′ Hα/Hβ ratio. This implies that the ionizing continua and NLR abundances in quasars are very similar.


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Copyright information

© Springer-Verlag 1988

Authors and Affiliations

  • Adam Wysota
    • 1
  • C. Martin Gaskell
    • 2
  1. 1.Astronomy Program, ESS BuildingState University of New YorkStony Brook
  2. 2.Astronomy Department, Dennison BuildingUniversity of MichiganAnn Arbor

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