Illuminating Dark Matter Halo Density Profiles Without Subhaloes
  Cold dark matter haloes consist of a relatively smooth dark matter component
as well as a system of bound subhaloes. It is the prevailing practice to
include all halo mass, including mass in subhaloes, in studies of halo density
profiles. However, often in observational studies satellites are treated as
having their own distinct dark matter density profiles in addition to the
profile of the host. This difference makes comparisons between theoretical and
observed results difficult. In this work we investigate density profiles of the
smooth components of host haloes by excluding mass contained within subhaloes.
We find that the density profiles of the smooth halo component (without
subhaloes) differs substantially from the conventional halo density profile.
Smooth profiles decline more rapidly at large radii and are not well
characterised by the standard NFW profile. We also find that concentrations
derived from smooth density profiles exhibit less scatter at fixed mass and a
weaker mass dependence than standard concentrations. Both smooth and standard
halo profiles can be described by a generalised Einasto profile, an Einasto
profile with a modified central slope, with smaller residuals than either an
NFW or Einasto profile. These results hold for both Milky Way-mass and
cluster-mass haloes. This new characterisation of smooth halo profiles can be
useful for many analyses, such as lensing and dark matter annihilation, in
which the smooth and clumpy components of a halo should be accounted for
separately.
