Black Hole Activities of Red Active Galactic Nuclei

  • Kim, Dohyeong (Astronomy Program, Department of Physics and Astronomy, Seoul National University) ;
  • Im, Myungshin (Astronomy Program, Department of Physics and Astronomy, Seoul National University) ;
  • Woo, Jong-Hak (Astronomy Program, Department of Physics and Astronomy, Seoul National University)
  • Published : 2015.04.10

Abstract

We investigate black hole (BH) activities of 16 red active galactic nuclei (AGNs). The 16 red AGNs selected by red colors in optical through near-infrared (NIR) and radio detection. In order to derive BH activities of the red AGNs, we use $P{\beta}$ line with NIR spectra obtained by the SpeX on the IRTF. The $P{\beta}$ line suffers from dust extinction less than UV/optical BH mass estimators. We compared Eddington ratios of the red AGNs and "normal" AGNs, and the Eddington ratios of red AGNs are significantly higher than those of "normal" AGNs. The result is consistent with a scenario that red AGNs are the intermediate population between star forming galaxies and "normal" AGNs, and BHs of red AGNs are very active and grow rapidly in such a stage.

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