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Foregrounds Derived from Maximum Entropy Method
(Synchrotron, Free-Free and Dust Maps)
HEALPix, nested, res 8 (Nside=256)
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:
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: