COMPARING THE WHITE DWARF COOLING SEQUENCES IN 47 Tuc AND NGC 6397

@article{Richer2013COMPARINGTW,
  title={COMPARING THE WHITE DWARF COOLING SEQUENCES IN 47 Tuc AND NGC 6397},
  author={Harvey B. Richer and Ryan Goldsbury and Jeremy Heyl and Jarrod Hurley and Aaron Dotter and Jason S. Kalirai and Kristin A. Woodley and Gregory G. Fahlman and Robert Michael Rich and Michael M. Shara},
  journal={The Astrophysical Journal},
  year={2013},
  volume={778},
  pages={104}
}
Using deep Hubble Space Telescope imaging, color-magnitude diagrams are constructed for the globular clusters 47 Tuc and NGC 6397. As expected, because of its lower metal abundance, the main sequence of NGC 6397 lies well to the blue of that of 47 Tuc. A comparison of the white dwarf cooling sequences of the two clusters, however, demonstrates that these sequences are indistinguishable over most of their loci—a consequence of the settling out of heavy elements in the dense white dwarf… 

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