Galactic foreground contributions to the 5-year Wilkinson Microwave Anisotropy Probe maps

We compute the cross-correlation between intensity and polarization from the 5-year Wilkinson Microwave Anisotropy Probe (WMAP5) data in different sky regions with respect to template maps for synchrotron, dust and freefree emission. We derive the frequency dependence and polarization fraction for all three components in 48 different sky regions of HEALPix (Nside= 2) pixelization. The anomalous emission associated with dust is clearly detected in intensity over the entire sky at the K (23-GHz) and Ka (33-GHz) WMAP bands, and is found to be the dominant foreground at low Galactic latitudes, between b =-40 degrees and +10 degrees. The synchrotron spectral index obtained from the K and Ka WMAP bands from an all-sky analysis is beta s=-3.32 +/- 0.12 for intensity and beta s=-3.01 +/- 0.03 for polarized intensity.