WMAP DR1 Foregrounds Derived from Maximum Entropy Method Description and Links

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/

Coordinate System:
Projection Type:
HEALPix, nested, res 8 (Nside=256)
Download Links:

The Maximum Entropy Method (MEM) is used to derive all-sky maps of the synchrotron, free-free and dust foregrounds at each of the 5 WMAP frequencies. Using the Smoothed I Maps minus the ILC map as input, representations of each of the foregrounds are fit to each pixel independently. The synchrotron and dust spectral indices are allowed to vary for each pixel, while the free-free spectral index is assumed to be constant over the sky. The MEM technique fits for the separate components by maximizing an entropy functional using the listed templates as priors:

Component Prior
Synchrotron Haslam 408 MHz
Free Free H-alpha Map
Dust FDS Map

The three model foregrounds are provided in separate files for each of the five WMAP frequencies. Note that the model temperatures are in mK, antenna temperature, rather than in thermodynamic units.

More details can be found in:

"First Year Wilkinson Microwave Anisotropy Probe (WMAP) Results:
Foreground Emission", Bennett, et al., 2003

WMAP Explanatory Supplement

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