The edge of the Galaxy

  title={The edge of the Galaxy},
  author={Alis J. Deason and Azadeh Fattahi and Carlos S. Frenk and Robert J. J. Grand and Kyle A. Oman and Shea Garrison-Kimmel and Christine M. Simpson and Julio F. Navarro},
  journal={Monthly Notices of the Royal Astronomical Society},
We use cosmological simulations of isolated Milky Way (MW)-mass galaxies, as well as Local Group (LG) analogues, to define the ‘edge’ – a caustic manifested in a drop in density or radial velocity – of Galactic-sized haloes, both in dark matter and in stars. In the dark matter, we typically identify two caustics: the outermost caustic located at ∼1.4r200m, corresponding to the ‘splashback’ radius, and a second caustic located at ∼0.6r200m, which likely corresponds to the edge of the virialized… Expand
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  • Physics
  • The Astrophysical Journal Letters
  • 2021
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