摘要
We derive deep luminosity functions (LFs) (to M <sub>z</sub> = -15) for galaxies in Abell 1835 (z = 0.25) and AC 114 (z = 0.31), and compare these with the local z′ LF for 69 clusters. The data show that the faint-end upturn, the excess of galaxies above a single Schechter function at M <sub>z</sub> < -17, does not exist in the higher redshift clusters. This suggests that the faint-end upturn galaxies have been created recently, by infall into clusters of star-forming field populations or via tidal disruption of brighter objects. © 2007 RAS.