Brightest Cluster Galaxy Formation in Low-Redshift Galaxy Clusters

Abstract

We present the composite luminosity function of a sample of 17 low-redshift galaxy clusters. Our luminosity functions have been measured for an inner region ($r\le r_{200}$) and an outer region ($r_{200}\le r\le 2r_{200}$) centred on each Brightest Cluster Galaxy. The inner region luminosity function has a significantly flatter faint-end slope (${\alpha }_{inner}=-1.81\pm 0.02$) than the outer region (${\alpha }_{outer}=-2.07\pm 0.02$). These results are consistent with the hypothesis that a large fraction of dwarf galaxies near cluster centres are being tidally disrupted.

4 pages, 1 figure, Contribution to "Tracing Cosmic Evolution with Galaxy Clusters" (Sesto2001), ASP Conference Series