Cosmological Constraints from Galaxy Clusters in the 2500 square-degree SPT-SZ Survey
Abstract
(abridged) We present cosmological constraints obtained from galaxy clusters identified by their Sunyaev-Zel'dovich effect signature in the 2500 square degree South Pole Telescope Sunyaev Zel'dovich survey. We consider the 377 cluster candidates identified at z>0.25 with a detection significance greater than five, corresponding to the 95% purity threshold for the survey. We compute constraints on cosmological models using the measured cluster abundance as a function of mass and redshift. We include additional constraints from multi-wavelength observations, including Chandra X-ray data for 82 clusters and a weak lensing-based prior on the normalization of the mass-observable scaling relations. Assuming a LCDM cosmology, where the species-summed neutrino mass has the minimum allowed value (mnu = 0.06 eV) from neutrino oscillation experiments, we combine the cluster data with a prior on H0 and find sigma_8 = 0.797+-0.031 and Omega_m = 0.289+-0.042, with the parameter combination sigma_8(Omega_m/0.27)^0.3 = 0.784+-0.039. These results are in good agreement with constraints from the CMB from SPT, WMAP, and Planck, as well as with constraints from other cluster datasets. Adding mnu as a free parameter, we find mnu = 0.14+-0.08 eV when combining the SPT cluster data with Planck CMB data and BAO data, consistent with the minimum allowed value. Finally, we consider a cosmology where mnu and N_eff are fixed to the LCDM values, but the dark energy equation of state parameter w is free. Using the SPT cluster data in combination with an H0 prior, we measure w = -1.28+-0.31, a constraint consistent with the LCDM cosmological model and derived from the combination of growth of structure and geometry. When combined with primarily geometrical constraints from Planck CMB, H0, BAO and SNe, adding the SPT cluster data improves the w constraint from the geometrical data alone by 14%, to w = -1.023+-0.042.
Keywords
Cite
@article{arxiv.1603.06522,
title = {Cosmological Constraints from Galaxy Clusters in the 2500 square-degree SPT-SZ Survey},
author = {T. de Haan and B. A. Benson and L. E. Bleem and S. W. Allen and D. E. Applegate and M. L. N. Ashby and M. Bautz and M. Bayliss and S. Bocquet and M. Brodwin and J. E. Carlstrom and C. L. Chang and I. Chiu and H-M. Cho and A. Clocchiatti and T. M. Crawford and A. T. Crites and S. Desai and J. P. Dietrich and M. A. Dobbs and A. N. Doucouliagos and R. J. Foley and W. R. Forman and G. P. Garmire and E. M. George and M. D. Gladders and A. H. Gonzalez and N. Gupta and N. W. Halverson and J. Hlavacek-Larrondo and H. Hoekstra and G. P. Holder and W. L. Holzapfel and Z. Hou and J. D. Hrubes and N. Huang and C. Jones and R. Keisler and L. Knox and A. T. Lee and E. M. Leitch and A. von der Linden and D. Luong-Van and A. Mantz and D. P. Marrone and M. McDonald and J. J. McMahon and S. S. Meyer and L. M. Mocanu and J. J. Mohr and S. S. Murray and S. Padin and C. Pryke and D. Rapetti and C. L. Reichardt and A. Rest and J. Ruel and J. E. Ruhl and B. R. Saliwanchik and A. Saro and J. T. Sayre and K. K. Schaffer and T. Schrabback and E. Shirokoff and J. Song and H. G. Spieler and B. Stalder and S. A. Stanford and Z. Staniszewski and A. A. Stark and K. T. Story and C. W. Stubbs and K. Vanderlinde and J. D. Vieira and A. Vikhlinin and R. Williamson and A. Zenteno},
journal= {arXiv preprint arXiv:1603.06522},
year = {2016}
}