A SUNYAEV-ZEL'DOVICH-SELECTED SAMPLE OF THE MOST MASSIVE GALAXY CLUSTERS IN THE 2500 deg²SOUTH POLE TELESCOPE SURVEY

Abstract

The South Pole Telescope (SPT) is currently surveying 2500 deg^2 of the\nsouthern sky to detect massive galaxy clusters out to the epoch of their\nformation using the Sunyaev-Zel'dovich (SZ) effect. This paper presents a\ncatalog of the 26 most significant SZ cluster detections in the full survey\nregion. The catalog includes 14 clusters which have been previously identified\nand 12 that are new discoveries. These clusters were identified in fields\nobserved to two differing noise depths: 1500 deg^2 at the final SPT survey\ndepth of 18 uK-arcmin at 150 GHz, and 1000 deg^2 at a depth of 54 uK-arcmin.\nClusters were selected on the basis of their SZ signal-to-noise ratio (S/N) in\nSPT maps, a quantity which has been demonstrated to correlate tightly with\ncluster mass. The S/N thresholds were chosen to achieve a comparable mass\nselection across survey fields of both depths. Cluster redshifts were obtained\nwith optical and infrared imaging and spectroscopy from a variety of ground-\nand space-based facilities. The redshifts range from 0.098 \\leq z \\leq 1.132\nwith a median of z_med = 0.40. The measured SZ S/N and redshifts lead to\nunbiased mass estimates ranging from 9.8 \\times 10^14 M_sun/h_70 \\leq\nM_200(rho_mean) \\leq 3.1 \\times 10^15 M_sun/h_70. Based on the SZ mass\nestimates, we find that none of the clusters are individually in significant\ntension with the LambdaCDM cosmological model. We also test for evidence of\nnon-Gaussianity based on the cluster sample and find the data show no\npreference for non-Gaussian perturbations.\n