A new population of extended, luminous star clusters in the halo of M31

  title={A new population of extended, luminous star clusters in the halo of M31},
  author={Avon P. Huxor and Nial R. Tanvir and Michael J. Irwin and Rodrigo A. Ibata and J. L. Collett and Annette M. N. Ferguson and Terry James Bridges and Geraint F. Lewis},
  journal={Monthly Notices of the Royal Astronomical Society},
We present three new clusters discovered in the halo of M31 which, although having globularlike colours and luminosities, have unusually large half-light radii, ∼30 pc. They lie at projected galactocentric distances of ≈15 to ≈35 kpc. These objects begin to fill the gap in parameter space between globular clusters and dwarf spheroidals, and are unlike any clusters found in the Milky Way, or elsewhere to date. Colour‐magnitude diagrams, integrated photometric properties and derived King profile… Expand

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