The Preferential Tidal Stripping of Dark Matter versus Stars in Galaxies
  Using high resolution hydrodynamical cosmological simulations, we conduct a
comprehensive study of how tidal stripping removes dark matter and stars from
galaxies. We find that dark matter is always stripped far more significantly
than the stars -- galaxies that lose $\sim$80$\%$ of their dark matter,
typically lose only 10$\%$ of their stars. This is because the dark matter halo
is initially much more extended than the stars. As such, we find the
stellar-to-halo size-ratio (measured using r$_{\rm{eff}}$/r$_{\rm{vir}}$) is a
key parameter controlling the relative amounts of dark matter and stellar
stripping. We use simple fitting formulae to measure the relation between the
fraction of bound dark matter and fraction of bound stars. We measure a
negligible dependence on cluster mass or galaxy mass. Therefore these formulae
have general applicability in cosmological simulations, and are ideal to
improve stellar stripping recipes in semi-analytical models, and/or to estimate
the impact that tidal stripping would have on galaxies when only their halo
mass evolution is known.
