Adaptive Optics Imaging and Spectroscopy of Cygnus A. I. Evidence for a Minor Merger

  title={Adaptive Optics Imaging and Spectroscopy of Cygnus A. I. Evidence for a Minor Merger},
  author={Gabriela Canalizo and Claire E. Max and David Harold. Whysong and Robert Antonucci and Scott E. Dahm},
  journal={The Astrophysical Journal},
We present Keck II adaptive optics near-infrared imaging and spectroscopic observations of the central regions of the powerful radio galaxy Cyg A. The 005 resolution images clearly show an unresolved nucleus between two spectacular ionization/scattering cones. We report the discovery of a relatively bright (K' ~ 19) secondary point source 04 or 400 pc in projection southwest of the radio nucleus. The object is also visible in archival Hubble Space Telescope optical images, although it is easily… 

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