Quantifying the smoothness of the stellar halo: a link to accretion history

  title={Quantifying the smoothness of the stellar halo: a link to accretion history},
  author={Lachlan Lancaster and Vasily A Belokurov and N. Wyn Evans},
  journal={Monthly Notices of the Royal Astronomical Society},
We investigate the utility of the 3-dimensional Two-Point Correlation Function (3D 2PCF) in quantifying substructure in the stellar halo of the Milky Way, particularly as a means of constraining the accretion history of our Galaxy. We use RR Lyrae variable stars from two different surveys as tracers of the structure in the Galactic stellar halo. We compare our measurements of the 3D 2PCF in these datasets to a suite of simulations of the formation of the stellar halo from Bullock and Johnston… 

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