Massive Cluster Surveys

ESA’s Planck Mission has provided a large, statistically representative sample of massive clusters, detected over the full sky (|b| > 15°) through their Sunyaev-Zel'dovich (SZ) effect. The Planck ESZ clusters are sufficiently X-ray bright that for all 165 z < 0.35 clusters, the proposed Chandra observations will collect 10,000 source counts that will be used to characterize each cluster’s dynamical state including merger properties, to measure cluster masses and mass proxies, and to define local cluster mass and temperature functions. Chandra observations will provide a benchmark at low redshifts for comparison to high redshift clusters and to cosmological N-body simulations.