The Atacama Cosmology Telescope: Cosmology from galaxy clusters detected via the Sunyaev-Zel'dovich effect

Neelima Sehgal, Hy Trac, Viviana Acquaviva, Peter A.R. Ade, Paula Aguirre, Mandana Amiri, John W. Appel, L. Felipe Barrientos, Elia S. Battistelli, J. Richard Bond, Ben Brown, Bryce Burger, Jay Chervenak, Sudeep Das, Mark J. Devlin, Simon R. Dicker, W. Bertrand Doriese, Joanna Dunkley, Rolando Dünner, Thomas Essinger-HilemanRyan P. Fisher, Joseph W. Fowler, Amir Hajian, Mark Halpern, Matthew Hasselfield, Carlos Hernández-Monteagudo, Gene C. Hilton, Matt Hilton, Adam D. Hincks, Renée Hlozek, David Holtz, Kevin M. Huffenberger, David H. Hughes, John P. Hughes, Leopoldo Infante, Kent D. Irwin, Andrew Jones, Jean Baptiste Juin, Jeff Klein, Arthur Kosowsky, Judy M. Lau, Michele Limon, Yen Ting Lin, Robert H. Lupton, Tobias A. Marriage, Danica Marsden, Krista Martocci, Phil Mauskopf, Felipe Menanteau, Kavilan Moodley, Harvey Moseley, Calvin B. Netterfield, Michael D. Niemack, Michael R. Nolta, Lyman A. Page, Lucas Parker, Bruce Partridge, Beth Reid, Blake D. Sherwin, Jon Sievers, David N. Spergel, Suzanne T. Staggs, Daniel S. Swetz, Eric R. Switzer, Robert Thornton, Carole Tucker, Ryan Warne, Ed Wollack, Yue Zhao

Research output: Contribution to journalArticlepeer-review


We present constraints on cosmological parameters based on a sample of Sunyaev-Zel'dovich-selected (SZ-selected) galaxy clusters detected in a millimeter-wave survey by the Atacama Cosmology Telescope. The cluster sample used in this analysis consists of nine optically confirmed high-mass clusters comprising the high-significance end of the total cluster sample identified in 455 deg2 of sky surveyed during 2008 at 148 GHz. We focus on the most massive systems to reduce the degeneracy between unknown cluster astrophysics and cosmology derived from SZ surveys. We describe the scaling relation between cluster mass and SZ signal with a four-parameter fit. Marginalizing over the values of the parameters in this fit with conservative priors gives σ8 = 0.851 ± 0.115 and w = -1.14 ± 0.35 for a spatially flat wCDM cosmological model with Wilkinson Microwave Anisotropy Probe (WMAP) seven-year priors on cosmological parameters. This gives a modest improvement in statistical uncertainty over WMAP seven-year constraints alone. Fixing the scaling relation between the cluster mass and SZ signal to a fiducial relation obtained from numerical simulations and calibrated by X-ray observations, we find σ8 = 0.821 ± 0.044 and w = -1.05 ± 0.20. These results are consistent with constraints from WMAP7 plus baryon acoustic oscillations plus Type Ia supernova which give σ8 = 0.802 ± 0.038 and w = -0.98 ± 0.053. A stacking analysis of the clusters in this sample compared to clusters simulated assuming the fiducial model also shows good agreement. These results suggest that, given the sample of clusters used here, both the astrophysics of massive clusters and the cosmological parameters derived from them are broadly consistent with current models.

Original languageEnglish (US)
Article number44
JournalAstrophysical Journal
Issue number1
StatePublished - May 1 2011
Externally publishedYes


  • cosmic background radiation
  • cosmology: observations
  • galaxies: clusters: general

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science


Dive into the research topics of 'The Atacama Cosmology Telescope: Cosmology from galaxy clusters detected via the Sunyaev-Zel'dovich effect'. Together they form a unique fingerprint.

Cite this