On the alleged duality of the Galactic halo

@article{Schoenrich2010OnTA,
  title={On the alleged duality of the Galactic halo},
  author={Ralph Schoenrich and Martin Asplund and Luca Casagrande},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2010},
  volume={415},
  pages={3807-3823}
}
We examine the kinematics of the Galactic halo based on SDSS/SEGUE data by Carollo et al. We find that their claims of a counter-rotating halo are the result of substantial biases in distance estimates (of the order of 50 per cent): the claimed retrograde component, which makes up only a tiny fraction of the entire sample, prone to contaminations, is identified as the tail of distance overestimates. The strong overestimates also result in a lift in the vertical velocity component, which… 
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