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Title: NINE-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE (WMAP) OBSERVATIONS: COSMOLOGICAL PARAMETER RESULTS

We present cosmological parameter constraints based on the final nine-year Wilkinson Microwave Anisotropy Probe (WMAP) data, in conjunction with a number of additional cosmological data sets. The WMAP data alone, and in combination, continue to be remarkably well fit by a six-parameter ΛCDM model. When WMAP data are combined with measurements of the high-l cosmic microwave background anisotropy, the baryon acoustic oscillation scale, and the Hubble constant, the matter and energy densities, Ω {sub b} h {sup 2}, Ω {sub c} h {sup 2}, and Ω{sub Λ}, are each determined to a precision of ∼1.5%. The amplitude of the primordial spectrum is measured to within 3%, and there is now evidence for a tilt in the primordial spectrum at the 5σ level, confirming the first detection of tilt based on the five-year WMAP data. At the end of the WMAP mission, the nine-year data decrease the allowable volume of the six-dimensional ΛCDM parameter space by a factor of 68,000 relative to pre-WMAP measurements. We investigate a number of data combinations and show that their ΛCDM parameter fits are consistent. New limits on deviations from the six-parameter model are presented, for example: the fractional contribution of tensor modes is limited tomore » r < 0.13 (95% CL); the spatial curvature parameter is limited to Ω{sub k} = -0.0027{sup +0.0039}{sub -0.0038}; the summed mass of neutrinos is limited to Σm {sub ν} < 0.44 eV (95% CL); and the number of relativistic species is found to lie within N {sub eff} = 3.84 ± 0.40, when the full data are analyzed. The joint constraint on N {sub eff} and the primordial helium abundance, Y {sub He}, agrees with the prediction of standard big bang nucleosynthesis. We compare recent Planck measurements of the Sunyaev-Zel'dovich effect with our seven-year measurements, and show their mutual agreement. Our analysis of the polarization pattern around temperature extrema is updated. This confirms a fundamental prediction of the standard cosmological model and provides a striking illustration of acoustic oscillations and adiabatic initial conditions in the early universe.« less
Authors:
;  [1] ; ; ;  [2] ;  [3] ;  [4] ;  [5] ;  [6] ; ;  [7] ; ;  [8] ;  [9] ;  [10] ; ;  [11] ;  [12] ;  [13] ;  [14] more »; « less
  1. Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T 1Z1 (Canada)
  2. Department of Physics and Astronomy, The Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218-2686 (United States)
  3. Max-Planck-Institut für Astrophysik, Karl-Schwarzschild Str. 1, D-85741 Garching (Germany)
  4. Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU, WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa 277-8583 (Japan)
  5. Oxford Astrophysics, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom)
  6. Canadian Institute for Theoretical Astrophysics, 60 St. George St., University of Toronto, Toronto, ON M5S 3H8 (Canada)
  7. ADNET Systems, Inc., 7515 Mission Dr., Suite A100 Lanham, MD 20706 (United States)
  8. Department of Physics, Jadwin Hall, Princeton University, Princeton, NJ 08544-0708 (United States)
  9. Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544-1001 (United States)
  10. University of Minnesota, School of Physics and Astronomy, 116 Church Street S.E., Minneapolis, MN 55455 (United States)
  11. Code 665, NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
  12. Columbia Astrophysics Laboratory, 550 W. 120th St., Mail Code 5247, New York, NY 10027-6902 (United States)
  13. Departments of Astrophysics and Physics, KICP and EFI, University of Chicago, Chicago, IL 60637 (United States)
  14. Department of Physics, Brown University, 182 Hope St., Providence, RI 02912-1843 (United States)
Publication Date:
OSTI Identifier:
22273338
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal, Supplement Series; Journal Volume: 208; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ANISOTROPY; ASTRONOMY; BACKGROUND RADIATION; BARYONS; COMPARATIVE EVALUATIONS; COSMOLOGICAL MODELS; COSMOLOGY; ENERGY DENSITY; LIMITING VALUES; NONLUMINOUS MATTER; NUCLEOSYNTHESIS; POLARIZATION; RELICT RADIATION; SPACE VEHICLES; TELESCOPES; TENSORS; UNIVERSE