The effect of tides on the Fornax dwarf spheroidal galaxy
  Estimates of the mass distribution and dark-matter (DM) content of dwarf
spheroidal galaxies (dSphs) are usually derived under the assumption that the
effect of the tidal field of the host galaxy is negligible over the radial
extent probed by kinematic data-sets. We assess the implications of this
assumption in the specific case of the Fornax dSph by means of N-body
simulations of a satellite orbiting around the Milky Way. We consider
observationally-motivated orbits and we tailor the initial distributions of the
satellite's stars and DM to match, at the end of the simulations, the observed
structure and kinematics of Fornax. In all our simulations the present-day
observable properties of Fornax are not significantly influenced by tidal
effects. The DM component is altered by the interaction with the Galactic field
(up to 20% of the DM mass within 1.6 kpc is lost), but the structure and
kinematics of the stellar component are only mildly affected even in the more
eccentric orbit (more than 99% of the stellar particles remain bound to the
dwarf). In the simulations that successfully reproduce Fornax's observables,
the dark-to-luminous mass ratio within 1.6 kpc is in the range 5-6, and up to
16-18 if measured within 3 kpc.
