The densest galaxy

  title={The densest galaxy},
  author={Jay Strader and Anil C. Seth and Duncan A Forbes and Giuseppina Fabbiano and Aaron J. Romanowsky and Jean P. Brodie and Charlie Conroy and Nelson Caldwell and Vincenzo Pota and Christopher Usher and Jacob A. Arnold},
  journal={The Astrophysical Journal},
We report the discovery of a remarkable ultra-compact dwarf galaxy around the massive Virgo elliptical galaxy NGC 4649 (M60), which we call M60-UCD1. With a dynamical mass of 2.0 × 10 8 M0 but a half-light radius of only ∼24 pc, M60-UCD1 is more massive than any ultra-compact dwarfs of comparable size, and is arguably the densest galaxy known in the local universe. It has a two-component structure well fit by a sum of S ´ ersic functions, with an elliptical, compact (rh = 14 pc; n ∼ 3.3) inner… 

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