A triple main sequence in the globular cluster NGC 2808

  title={A triple main sequence in the globular cluster NGC 2808},
  author={Giampaolo Piotto and Luigi R. Bedin and Jay Barry Anderson and Ivan R. King and Santi Cassisi and Antonino P. Milone and Sandro Villanova and Adriano Pietrinferni and Alvio Renzini},
  journal={The Astrophysical Journal},
Accurate photometry with HST's ACS shows that the main sequence (MS) of the globular cluster NGC 2808 splits into three separate branches. The three MS branches may be associated with the complexities of the cluster's horizontal branch and of its abundance distribution. We attribute the MS branches to successive rounds of star formation, with different helium abundances; we discuss possible sources of helium enrichment. Some other massive globulars also appear to have complex populations; we… 
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The peculiar horizontal branch of NGC 2808
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Multiple Sequences of M-dwarfs in NGC 2808 and ω Centauri.
  • A. Milone
  • Physics
    Proceedings of the International Astronomical Union
  • 2012
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