Wilkinson Microwave Anisotropy Probe

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Product Name
Intensity and Polarization Exclusion Masks
Coord. System
Projection Type
HEALPix, nested, res 9 (Nside=512), res 10 (Nside=1024), res 4 (Nside=16)


A number of WMAP data analysis applications use pixel masks which exclude foreground-contaminated portions of the sky from the analysis. Diffuse emission is masked using a combination of cuts in the K band map and a model of thermal dust emission. Point sources are masked based on a combination of external catalog data and WMAP-detected sources. A source exclusion radius of 0.6 degree is used for the intensity masks and 1.0 degrees for the polarization masks.

Mask sky cut
Kp2 Intensity 15.3 The standard intensity mask.
Kp0 Intensity 23.5 A more aggressive intensity mask.
Processing 5.7 The mask used in map-making.
Source Only 2.4 The point source intensity mask.
Polarization 26.5 The standard polarization mask (P06).
P04 Polarization 31.1 A more aggressive polarization mask.
P02 Polarization 44.6 A more aggressive polarization mask.
Polarization Sources 0.2 The point source polarization mask.

Mask values for each map pixel are provided in the N_obs field of the data file (the 'Temperature' field is set to zero for all pixels). A mask value of zero means the pixel is rejected; a value of one means the pixel is accepted.

Additional Information

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