Wandering Stars: an Origin of Escaped Populations
  We demonstrate that stars beyond the virial radii of galaxies may be
generated by the gravitational impulse received by a satellite as it passes
through the pericenter of its orbit around its parent. These stars may become
energetically unbound (escaped stars), or may travel to further than a few
virial radii for longer than a few Gyr, but still remain energetically bound to
the system (wandering stars). Larger satellites (10-100% the mass of the
parent), and satellites on more radial orbits are responsible for the majority
of this ejected population. Wandering stars could be observable on Mpc scales
via classical novae, and on 100 Mpc scales via SNIa. The existence of such
stars would imply a corresponding population of barely-bound, old, high
velocity stars orbiting the Milky Way, generated by the same physical mechanism
during the Galaxy's formation epoch. Sizes and properties of these combined
populations should place some constraints on the orbits and masses of the
progenitor objects from which they came, providing insight into the merging
histories of galaxies in general and the Milky Way in particular.
