Dark matter concentrations and a search for cores in Milky Way dwarf
  satellites
  We investigate the mass distributions within eight classical Milky Way dwarf
spheroidal galaxies (MW dSphs) using an equilibrium Jeans analysis and we
compare our results to the mass distributions predicted for subhalos in
dissipationless \Lambda CDM simulations. In order to match the dark matter
density concentrations predicted, the stars in these galaxies must have a
fairly significant tangential velocity dispersion anisotropy (\beta ~-1.5). For
the limiting case of an isotropic velocity dispersion (\beta =0), the classical
MW dSphs predominantly prefer to live in halos that are less concentrated than
\Lambda CDM predictions. We also investigate whether the dSphs prefer to live
in halos with constant density cores in the limit of isotropic velocity
dispersion. Interestingly, even in this limit, not all of the dSphs prefer
large constant-density cores: the Sculptor dSph prefers a cusp while Carina,
Draco and Leo I prefer cores. The other four dSphs do not show a statistically
significant preference for either cuspy or cored profiles. Finally, we
re-examine the hypothesis that the density profiles of these eight MW dSphs can
be quantified by a common dark matter halo.
