Icarus: A Flat and Fast Prograde Stellar Stream in the Milky Way Disk

  title={Icarus: A Flat and Fast Prograde Stellar Stream in the Milky Way Disk},
  author={Paola Re Fiorentin and Alessandro Spagna and Mario Gilberto Lattanzi and Michele Cignoni},
  journal={The Astrophysical Journal Letters},
We explore the local volume of the Milky Way via chemical and kinematical measurements from high-quality astrometric and spectroscopic data recently released by the Gaia, APOGEE, and GALAH programs. We chemically select 1137 stars up to 2.5 kpc of the Sun and [Fe/H] ≤ −1.0 dex, and find evidence of statistically significant substructures. Clustering analysis in velocity space classifies 163 objects into eight kinematical groups, whose origin is further investigated with high-resolution N-body… 
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