Hiding in plain sight: record-breaking compact stellar systems in the Sloan Digital Sky Survey

  title={Hiding in plain sight: record-breaking compact stellar systems in the Sloan Digital Sky Survey},
  author={Michael Alexander Sandoval and Richard Vo and Aaron J. Romanowsky and Jay Strader and Jieun Choi and Zachary G. Jennings and Charlie Conroy and Jean P. Brodie and Caroline Foster and Alexa Villaume and Mark A. Norris and Joachim Janz and Duncan A Forbes},
  journal={arXiv: Astrophysics of Galaxies},
Motivated by the recent, serendipitous discovery of the densest known galaxy, M60-UCD1, we present two initial findings from a follow-up search, using the Sloan Digital Sky Survey, Subaru/Suprime-Cam and Hubble Space Telescope imaging, and SOuthern Astrophysical Research (SOAR)/Goodman spectroscopy. The first object discovered, M59-UCD3, has a similar size to M60-UCD1 (half-light radius of r_h ~ 20 pc) but is 40% more luminous (M_V ~ -14.6), making it the new densest-known galaxy. The second… 
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