Action-based models for dwarf spheroidal galaxies and globular clusters
  A new family of self-consistent DF-based models of stellar systems is
explored. The stellar component of the models is described by a distribution
function (DF) depending on the action integrals, previously used to model the
Fornax dwarf spheroidal galaxy (dSph). The stellar component may cohabit with
either a dark halo, also described by a DF, or with a massive central black
hole. In all cases we solve for the model's self-consistent potential.
Focussing on spherically symmetric models, we show how the stellar observables
vary with the anisotropy prescribed by the DF, with the dominance and nature of
the dark halo, and with the mass of the black hole. We show that precise fits
to the observed surface brightness profiles of four globular clusters can be
obtained for a wide range of prescribed velocity anisotropies. We also obtain
precise fits to the observed projected densities of four dSphs. Finally, we
present a three-component model of the Scupltor dSph with distinct DFs for the
red and blue horizontal branch stars and the dark matter halo.
