galaxies near clusters

Sheldon (with some help from Masjedi) has done a very nice job of statistically background-subtracting the galaxy populations around the BCG clusters identified in the SDSS imaging data. These clusters are at redshifts higher than those measured in the SDSS Main Sample so he can only identify the members statistically, but because he has enormous numbers of clusters and enormous amounts of sky for control samples, he gets incredibly high signal-to-noise color-magnitude diagrams as a function of cluster richness and angular separation from the center of the cluster. He confirms all the things we know about galaxy environments but at much higher precision. The big question is whether we can use the new precision to see new things. We discussed that today.