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Nine-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Parameter ResultsWe 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 Lambda-CDM 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 Omega(sub b)h(exp 2), Omega(sub c)h(exp 2)and Omega(sub Lambda), are each determined to a precision of approx. 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 5 sigma 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 Lambda-CDM parameter space by a factor of 68,000 relative to pre-WMAP measurements. We investigate a number of data combinations and show that their Lambda-CDM 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 to r < 0.13 (95% CL); the spatial curvature parameter is limited to Omega(sub kappa) = (0.0027 (sub +0.0039) (sup −0.0038;) the summed mass of neutrinos is limited to Sigma M(sub nu) < 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.
Document ID
20140011030
Acquisition Source
Goddard Space Flight Center
Document Type
Reprint (Version printed in journal)
Authors
Hinshaw, G.
(British Columbia Univ. Vancouver, British Columbia, Canada)
Larson, D.
(Johns Hopkins Univ. Baltimore, MD, United States)
Komatsu, E.
(Max-Planck-Inst. fuer Astrophysik Garching, Germany)
Spergel, D. N.
(Tokyo Univ. Kashiwa, Japan)
Bennett, C. L.
(Johns Hopkins Univ. Baltimore, MD, United States)
Dunkley, J.
(Oxford Univ. Oxford, United Kingdom)
Nolta, M. R.
(Toronto Univ. Ontario, Canada)
Halpern, M.
(British Columbia Univ. Vancouver, British Columbia, Canada)
Hill, R. S.
(Adnet Systems, Inc. Lanham, MD, United States)
Odegard, N.
(Adnet Systems, Inc. Lanham, MD, United States)
Page, L.
(Princeton Univ. NJ, United States)
Smith, K. L.
(Princeton Univ. NJ, United States)
Weiland, J. L.
(Johns Hopkins Univ. Baltimore, MD, United States)
Gold, B.
(Minnesota Univ. Minneapolis, MN, United States)
Jarosik, N.
(Princeton Univ. NJ, United States)
Kogut, A.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Limon, M.
(Columbia Univ. New York, NY, United States)
Meyer, S. S.
(Chicago Univ. Chicago, IL, United States)
Tucker, G. S.
(Brown Univ. Providence, RI, United States)
Wollack, E.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Wright, E. L.
(California Univ. Los Angeles, CA, United States)
Date Acquired
August 26, 2014
Publication Date
October 1, 2013
Publication Information
Publication: The Astrophysical Journal Supplement Series, 208:19 2013 October
Publisher: IOP Publishing
Volume: 208
Issue: 2
Subject Category
Astrophysics
Report/Patent Number
GSFC-E-DAA-TN11455
Funding Number(s)
CONTRACT_GRANT: NSf PHY-0758153
CONTRACT_GRANT: NSF AST-0807649
CONTRACT_GRANT: NNX08AL43G
CONTRACT_GRANT: NNX09AC98A
CONTRACT_GRANT: NNX11AD25G
Distribution Limits
Public
Copyright
Public Use Permitted.
Keywords
cosmology
early universe
space vehicles
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