Diffuse optical intracluster light as a measure of stellar tidal
  stripping: the cluster CL0024+17 at $z\sim $0.4 observed at LBT
  We have evaluated the diffuse intracluster light (ICL) in the central core of
the galaxy cluster CL0024+17 at $z\sim 0.4$ observed with the prime focus
camera (LBC) at LBT. The measure required an accurate removal of the galaxies
light within $\sim 200$ kpc from the center. The residual background intensity
has then been integrated in circular apertures to derive the average ICL
intensity profile. The latter shows an approximate exponential decline as
expected from theoretical cold dark matter models. The radial profile of the
ICL over the galaxies intensity ratio (ICL fraction) is increasing with
decreasing radius but near the cluster center it starts to bend and then
decreases where the overlap of the halos of the brightest cluster galaxies
becomes dominant. Theoretical expectations in a simplified CDM scenario show
that the ICL fraction profile can be estimated from the stripped over galaxy
stellar mass ratio in the cluster. It is possible to show that the latter
quantity is almost independent of the properties of the individual host
galaxies but mainly depends on the average cluster properties. The predicted
ICL fraction profile is thus very sensitive to the assumed CDM profile, total
mass and concentration parameter of the cluster. Adopting values very similar
to those derived from the most recent lensing analysis in CL0024+17 we find a
good agreement with the observed ICL fraction profile. The galaxy counts in the
cluster core have then been compared with that derived from composite cluster
samples in larger volumes, up to the clusters virial radius. The galaxy counts
in the CL0024+17 core appear flatter and the amount of bending respect to the
average cluster galaxy counts imply a loss of total emissivity in broad
agreement with the measured ICL fraction.
