Velocity dispersion profiles of seven dwarf spheroidal galaxies

  title={Velocity dispersion profiles of seven dwarf spheroidal galaxies},
  author={Matthew G. Walker and Mario L. Mateo and E. Olszewski and Oleg Y. Gnedin and Xiao Wang and Bodhisattva Sen and Michael Woodroofe},
  journal={The Astrophysical Journal},
We present stellar velocity dispersion profiles for seven Milky Way dwarf spheroidal (dSph) satellite galaxies. We have measured 8394 line-of-sight velocities (±2.5 km s-1) for 6804 stars from high-resolution spectra obtained at the Magellan and MMT telescopes. We combine these new data with previously published velocities to obtain the largest available kinematic samples, which include more than 5500 dSph members. All the measured dSphs have stellar velocity dispersion of order 10 km s-1 that… Expand

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