The Close Environment of Seyfert Galaxies and Its Implication for Unification Models

  title={The Close Environment of Seyfert Galaxies and Its Implication for Unification Models},
  author={Deborah Dultzin-Hacyan and Yair Krongold and Ivette Fuentes-guridi and Paolo Marziani},
  journal={The Astrophysical Journal},
In this Letter, we present a statistical analysis of the circumgalactic environment of nearby Seyfert galaxies based on a computer-aided search of companion galaxies on the Digitized Sky Survey. We defined a sample of 72 nearby Seyfert 1 galaxies (redshift 0.007≤z≤0.034) and a sample of 60 Seyfert 2 galaxies (0.007≤z≤0.020), which include only high galactic latitude objects. In addition, we built two control samples of nonactive galaxies that match the number of sample members, the redshift… 

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