Surface photometry of brightest cluster galaxies and intracluster stars in ΛCDM

We simulate the phase-space distribution of stellar mass in nine massive Lambda cold dark matter galaxy clusters by applying the semi-analytic particle tagging method of Cooper et al. to the Phoenix suite of high-resolution N-body simulations (M-200 approximate to 7.5-33 x 10(14) M-circle dot). The resulting surface brightness (SB) profiles of brightest cluster galaxies (BCGs) matchwell to observations. On average, stars formed in galaxies accreted by the BCG account for greater than or similar to 90 per cent of its total mass (the remainder is formed in situ). In circular BCG-centred apertures, the superposition of multiple debris clouds (each greater than or similar to 10 per cent of the total BCG mass) from different progenitors can result in an extensive outer diffuse component, qualitatively similar to a 'cD envelope'. These clouds typically originate from tidal stripping at z less than or similar to 1 and comprise both streams and the extended envelopes of other massive galaxies in the cluster. Stars at very low SB contribute a significant fraction of the total cluster stellar mass budget: in the central 1 Mpc(2) of a z similar to 0.15 cluster imaged at SDSS-like resolution, our fiducial model predicts 80-95 per cent of stellar mass below a SB of mu(V) similar to 26.5 mag arcsec(-2) is associated with accreted stars in the envelope of the BCG. The ratio of BCG stellar mass (including this diffuse component) to total cluster stellar mass is similar to 30 per cent.