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QUIET 1st+2nd Season Galactic Field Data

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The QUIET map and mask data are stored in standard HEALPix FITS format.

The QUIET noise covariance matrices are stored in cut-sky format, including only unmasked (Stokes Q and U) pixels. The full matrix can this be represented as a 2x2 block matrix on the form

N = (QQ, QU) (UQ, UU)

Units are thermodynamic microkelvin2

Each matrix is stored in a standard HDF format, containing the following datasets:

  • Inverse - boolean flag indicating whether the matrix is an inverse; 0 in our case.
  • Nside - HEALPix resolution parameter, equal to 512 in our case.
  • Ordering - HEALPix ordering scheme, equal to 2 (NESTED) in our case.
  • pixels - List of HEALPix pixels.
  • cov - Actual noise covariance matrix stored in a (2,npix,2,npix) array, where the first and third entries run over Stokes parameters, and the second and fourth over pixels.

The QUIET maps, QUIET+WMAP maps, and associated covariance matrices follow the CMB polarization convention.

For general information on how to read HDF files, see

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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
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