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WMAP

Wilkinson Microwave Anisotropy Probe

The data made available through this page has been updated. The most recent version of this data may be accessed through /product/map/current/

Product Name
Cosmological Parameters
Mission
WMAP

Description

Analysis of the WMAP data involved the computation of cosmological parameters assuming a variety of models and including a variety of datasets in addition to the WMAP dataset. The various model/dataset combinations that were tested are displayed in a matrix; the combinations that were analyzed have links in the corresponding cells to individual display pages that show the cosmological parameters computed using that combination of model and dataset. A printable version of each list of parameters is made available as a Postscript file through a link its corresponding the individual display page.

Mnemonics are used to identify the models and datasets in the table and the individual model/dataset displays. The following table translate the mnemonics:

Models
Mnemonic Description Mnemonic Description
LCDM ΛCDM ISO1 Anticorrelated CDM isocurvature.
WCDM Dark energy equation of state (w) allowed to vary. ISO2 Uncorrelated CDM isocurvature.
OLCDM ΩK allowed to vary. MNU Massive neutrinos.
OWCDM ΩK and w allowed to vary. NREL Number of relativistic species.
LENS Turn on lensing when computing CMB spectrum. RUN Running spectral index.
SZ Floating amplitude for SZ spectrum. TENS Tensor modes.


XE Two step reionization model.
Datasets
Mnemonic Description
WMAP WMAP 5 year data set
2DF 2dF Galaxy Redshift Survey (Cole, et.al., 2005)
SDSS Sloan Digital Sky Survey, (Tegmark, et.al., 2004; Eisenstein, et.al., 2005)
ACB ACBAR--complete data set (Reichardt, et.al., 2008)
BAO Baryonic Acoustic Oscillations (2dF+SDSS combination, Percival 2007)
EBAO Eisenstein Baryonic Acoustic Oscillations (SDSS/LRG subsample of BAO)
SNALL Supernova "Gold Sample" (Riess, et.al., 2004), Supernova Legacy Survey (SNLS, Astier, et.al., 2005), and SNEssence
HST Hubble Space Telescope Key Project (Freedman, et.al., 2001)
CMB Boomerang + CBI + VSA + Acbar 2006
LRG Sloan Luminous Red Galaxy Sample (Tegmark 2006)
LYAPOST Post-processed with the Lyman-alpha forest data (Seljak, Slosar, and McDonald, 2006)

As mentioned previously, each model/dataset combination has an individual display page that shows the WMAP measurements of the cosmological parameters, with a link to a Postscript file showing the same parameters. These display pages also contain links to files containing WMAP's best fit Cl's, best fit matter power spectra, and Monte Carlo Markov Chains. The Markov Chain are supplied in a compressed tarball that contains a README file describing the contents. The spectra files contain:

  • Best fit Cl scalar files contain four columns: l, TT, EE, and TE. The tensor and total files contain five columns: l, TT, EE, BB, and TE. The Cl columns are scaled: T02 l (l + 1) Cl / 2&pi in µK2;
  • Best fit matter power spectra files contain two columns. The first column is k/h in units of Mpc-1. The second column is the linear matter power spectrum P(k), defined such that the variance is: σ2 = (2π)-3 ∫d3k P(k)

Additional Information

  • Cole, et.al., 2005, MNRAS, 362, 505
  • Eisenstein, et.al., 2005, ApJ, 633, 560
  • Kuo, et.al., 2004, ApJ, 600, 32
  • Readhead, et.al., 2004, ApJ, 609, 498
  • Dickinson, et.al., 2004, MNRAS, 353, 732
  • Freedman, et.al., 2004, ApJ, 553, 47
  • Tegmark, et.al., 2004, ApJ, 606, 702
  • Astier, et.al., 2006, AA, 447, 31
  • Riess, et.al., 2004, ApJ, 607, 665

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A service of the HEASARC and of the Astrophysics Science Division at NASA/GSFC
Goddard Space Flight Center, National Aeronautics and Space Administration
HEASARC Director: Dr. Alan P. Smale
LAMBDA Director: Dr. Eric R. Switzer
NASA Official: Dr. Eric R. Switzer
Web Curator: Mr. Michael R. Greason