  We present an analysis of the foreground emission present in the WMAP 3-year
data as determined by the method of Independent Component Analysis. We derived
coupling coefficients between the WMAP data and foreground templates which are
then used to infer the spectral behaviour for three foreground components --
synchrotron, anomalous dust-correlated emission and free-free. For the first
two components, we find values consistent with previous results although
slightly steeper. We confirm the inconsistency in the scaling between the Ha
template and free-free emission at K- and Ka-bands where an electron
temperature of ~ 4000 K is indicated. We also see evidence of significantly
flatter spectral behaviour to higher frequencies than expected theoretically
and previously noted by Dobler et al.(2008a), but only when analysing the Kp2
sky coverage. We further apply FASTICA 'iteratively', using data pre-cleaned
using foreground templates scaled to the WMAP frequencies by coupling
coefficients determined by a prior FASTICA analysis. This multi-frequency
analysis allows us to determine the presence of residual foreground emission
not traced by the templates. We confirm the existence of a component spatially
distributed along the Galactic plane and particularly enhanced near the center
(the 'WMAP haze'). This emission is less extended when using the WMAP K-Ka data
as the synchrotron template confirming that it can be considered a better
template for foreground cleaning of the WMAP data. However its use complicates
the physical interpretation of the nature of the foreground emission and
residuals. since it contains a mixture of several, physically distinct emission
mechanisms.
