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WMAP DR1 LCDM Theoretical Power Spectra

The data made available through this page has been updated. The most recent version of this data may be accessed through https://lambda.gsfc.nasa.gov/product/wmap/current/

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Selected theoretical power spectra computed using the CMBFast code that was used in the WMAP parameter analysis. Three representative spectra are provided, along with the parameter sets used to generate them:

  • LCDM model using a scale-dependent (running) primordial spectral index which best fits the WMAP, CBI and ACBAR CMB data.
  • LCDM model using a power law for the primordial spectral index which best fits the WMAP, CBI and ACBAR CMB data.
  • LCDM model using a scale-dependent (running) primordial spectral index which best fits the WMAP, CBI and ACBAR CMB data, plus the 2dF and Lyman-alpha data.

For each of the three model parameter sets, the TT, TE and EE model power spectra are provided as an ASCII table containing the following four columns:

  • the multipole moment l
  • the TT model power spectrum, l(l+1)C_l/2pi, in units of uK2
  • the TE model power spectrum, l(l+1)C_l/2pi, in units of uK2
  • the EE model power spectrum, l(l+1)C_l/2pi, in units of uK2

Note that EE data were not included in the model fits, so the EE spectrum should be regarded as a prediction.

For those who would like to use these models as inputs to SYNFAST (a HEALPix FORTRAN facility which computes a skymap realization from an input power spectrum), compatible FITS-formatted versions of the three models are also provided. Note that, in keeping with the SYNFAST convention, the FITS files contain C_l rather than l(l+1)C_l/2pi.

More details can be found in:

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