The Accretion Origin of the Milky Way’s Stellar Halo

  title={The Accretion Origin of the Milky Way’s Stellar Halo},
  author={Eric F. Bell and Daniel B. Zucker and Vasily A Belokurov and Sanjib Sharma and Kathryn V. Johnston and James S Bullock and David W. Hogg and Knud Jahnke and Jelte T.A. de Jong and Timothy C. Beers and N. Wyn Evans and Eva K. Grebel and Željko Ivezi{\'c} and Sergey E. Koposov and Hans-Walter Rix and Donald P. Schneider and Matthias Steinmetz and A. M. Zolotov},
  journal={The Astrophysical Journal},
We have used data from the Sloan Digital Sky Survey (SDSS) Data Release 5 to explore the overall structure and substructure of the stellar halo of the Milky Way using ~4 million color-selected main-sequence turnoff stars with -->0.2 18.5 ? r 0.5 3.7 ? 1.2 ? 108 M?. The density profile of the stellar halo is approximately -->? r??, where ? -->2 > ? > ? 4. Yet, we found that all smooth and symmetric models were very poor fits to the distribution of stellar halo stars because the data exhibit a… Expand

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