WMAP data when combined with ancillary data on free-free , synchrotron and dust allow an improved understanding of the spectrum of emission from each of these components .
Here we examine the sky variation at intermediate latitudes using a cross-correlation technique .
In particular , we compare the observed emission in 15 selected sky regions to three “ standard ” templates .

The free-free emission of the diffuse ionised gas is fitted by a well-known spectrum at K and Ka band , but the derived emissivity corresponds to a mean electron temperature of \sim 4000 - 5000 K. This is inconsistent with estimates from galactic H ii regions although a variation in the derived ratio of H \alpha to free-free intensity by a factor of \sim 2 is also found from region to region .
The origin of the discrepancy is unclear .

The anomalous emission associated with dust is clearly detected in most of the 15 fields studied .
Fields that are only weakly contaminated by synchrotron , free-free and CMB are studied ; the anomalous emission correlates well with the Finkbeiner et al .
( 1999 ) model 8 predictions ( FDS8 ) at 94 GHz , with an effective spectral index between 20 and 60 GHz , of \beta \sim - 2.85 .
Furthermore , the emissivity varies by a factor of \sim 2 from cloud to cloud .
A modestly improved fit to the anomalous dust at K-band is provided by modulating the template by an estimate of the dust colour temperature , specifically FDS8 \times { T } ^ { n } .
We find a preferred value n \sim 1.6 , although there is a scatter from region to region .
Nevertheless , the preferred index drops to zero at higher frequencies where the thermal dust emission dominates .

The synchrotron emission steepens between GHz frequencies and the WMAP bands .
There are indications of spectral index variations across the sky but the current data are not precise enough to accurately quantify this from region-to-region .

Our analysis of the WMAP data indicates strongly that the dust-correlated emission at the low WMAP frequencies has a spectrum which is compatible with spinning dust ; we find no evidence for a synchrotron component correlated with dust .
The importance of these results for the correction of CMB data for Galactic foreground emission is discussed .