Probing Satellite Halos with Weak Gravitational Lensing
  We demonstrate the possibility of detecting tidal stripping of dark matter
subhalos within galaxy groups using weak gravitational lensing. We have run
ray-tracing simulations on galaxy catalogues from the Millennium Simulation to
generate mock shape catalogues. The ray-tracing catalogues assume a halo model
for galaxies and groups, using various models with different distributions of
mass between galaxy and group halos to simulate different stages of group
evolution. Using these mock catalogues, we forecast the lensing signals that
will be detected around galaxy groups and satellite galaxies, as well as test
two different methods for isolating the satellites' lensing signals. A key
challenge is to determine the accuracy to which group centres can be
identified. We show that with current and ongoing surveys, it will possible to
detect stripping in groups of mass 10^12--10^15 Msun.
