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Title: The Atacama Cosmology Telescope: cosmological parameters from three seasons of data

We present constraints on cosmological and astrophysical parameters from high-resolution microwave background maps at 148 GHz and 218 GHz made by the Atacama Cosmology Telescope (ACT) in three seasons of observations from 2008 to 2010. A model of primary cosmological and secondary foreground parameters is fit to the map power spectra and lensing deflection power spectrum, including contributions from both the thermal Sunyaev-Zeldovich (tSZ) effect and the kinematic Sunyaev-Zeldovich (kSZ) effect, Poisson and correlated anisotropy from unresolved infrared sources, radio sources, and the correlation between the tSZ effect and infrared sources. The power ℓ{sup 2}C{sub ℓ}/2π of the thermal SZ power spectrum at 148 GHz is measured to be 3.4±1.4  μK{sup 2} at ℓ = 3000, while the corresponding amplitude of the kinematic SZ power spectrum has a 95% confidence level upper limit of 8.6  μK{sup 2}. Combining ACT power spectra with the WMAP 7-year temperature and polarization power spectra, we find excellent consistency with the LCDM model. We constrain the number of effective relativistic degrees of freedom in the early universe to be N{sub eff} = 2.79±0.56, in agreement with the canonical value of N{sub eff} = 3.046 for three massless neutrinos. We constrain the sum of the neutrino masses tomore » be Σm{sub ν} < 0.39 eV at 95% confidence when combining ACT and WMAP 7-year data with BAO and Hubble constant measurements. We constrain the amount of primordial helium to be Y{sub p} = 0.225±0.034, and measure no variation in the fine structure constant α since recombination, with α/α{sub 0} = 1.004±0.005. We also find no evidence for any running of the scalar spectral index, dn{sub s}/dln k = −0.004±0.012.« less
Authors:
;  [1] ;  [2] ; ; ;  [3] ;  [4] ; ; ; ;  [5] ;  [6] ; ;  [7] ;  [8] ;  [9] ;  [10] ;  [11] ;  [12] ;  [13] more »; « less
  1. Joseph Henry Laboratories of Physics, Jadwin Hall, Princeton University, Princeton, NJ 08544 (United States)
  2. Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544 (United States)
  3. Canadian Institute for Theoretical Astrophysics, University of Toronto, Toronto, ON M5S 3H8 (Canada)
  4. New York City College of Technology, 300 Jay Street, Brooklyn, NY 11201 (United States)
  5. Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T 1Z4 (Canada)
  6. School of Physics and Astronomy, Cardiff University, The Parade, Cardiff, Wales CF24 3AA (United Kingdom)
  7. Departamento de Astronomía y Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, Casilla 306, Santiago 22 (Chile)
  8. Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260 (United States)
  9. Department of Astrophysics, Oxford University, Oxford OX1 3RH (United Kingdom)
  10. Code 553/665, NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
  11. Department of Physics and Astronomy, The Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218-2686 (United States)
  12. High Energy Physics Division, Argonne National Laboratory, 9700 S Cass Avenue, Lemont IL 60439 (United States)
  13. Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States)
Publication Date:
OSTI Identifier:
22369964
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2013; Journal Issue: 10; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTROPHYSICS; COSMOLOGY; DEGREES OF FREEDOM; EVOLUTION; GHZ RANGE 100-1000; GRAVITATIONAL LENSES; HELIUM; MICROWAVE RADIATION; NEUTRINOS; RECOMBINATION; SPECTRA; TELESCOPES