Matching the dark matter profiles of dSph galaxies with those of
  simulated satellites: a two parameter comparison
  We compare the dark matter halos' structural parameters derived for four
Milky Way dwarf spheroidal galaxies to those of subhalos found in cosmological
$N$-body simulations. We confirm that estimates of the mass at a single fixed
radius are fully consistent with the observations. However, when a second
structural parameter such as the logarithmic slope of the dark halo density
profile measured close to the half-light radius is included in the comparison,
we find little to no overlap between the satellites and the subhalos. Typically
the right mass subhalos have steeper profiles at these radii than measurements
of the dSph suggest. Using energy arguments we explore if it is possible to
solve this discrepancy by invoking baryonic effects. Assuming that feedback
from supernovae can lead to a reshaping of the halos, we compute the required
efficiency and find entirely plausible values for a significant fraction of the
subhalos and even as low as 0.1%. This implies that care must be taken not to
exaggerate the effect of supernovae feedback as this could make the halos too
shallow. These results could be used to calibrate and possibly constrain
feedback recipes in hydrodynamical simulations.
