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We present a pilot study on the origin and assembly history of the intracluster starlight (ICL) for four galaxy clusters at 0.44 z 0.57 observed with the Hubble Space Telescope from the Cluster Lensing and Supernova Survey with Hubble (CLASH) sample. Using this sample of CLASH clusters we set an empirical limit on the amount of scatter in ICL surface brightness profiles of such clusters at z = 0.5, a mean of 0.24 mag arcsec -2 for 10 11 Gyr. Such negative colour (and equivalently, metallicity) gradients can arise from tidal stripping of L * galaxies and/or the disruption of dwarf galaxies, but not major mergers with the BCG. We also find that the ICL at 110 kpc has a colour comparable to m * + 2 red sequence galaxies, suggesting that out to this radius the ICL is dominated by stars liberated from galaxies with L > 0.2 L * . Finally, we find ICL luminosities of 4-8 L * in the range 10 0.2L * galaxies, and disfavour significant contribution to the ICL by dwarf disruption or major mergers with the BCG.
DeMaio et al. (Tue,) studied this question.