Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations:   Galactic Foreground Emission
  We present a new estimate of foreground emission in the WMAP data, using a Markov chain Monte Carlo (MCMC) method. The new technique delivers maps of each foreground component for a variety of foreground models, error estimates of the uncertainty of each foreground component, and provides an overall goodness-of-fit measurement. The resulting foreground maps are in broad agreement with those from previous techniques used both within the collaboration and by other authors.   We find that for WMAP data, a simple model with power-law synchrotron, free-free, and thermal dust components fits 90% of the sky with a reduced chi-squared of 1.14. However, the model does not work well inside the Galactic plane. The addition of either synchrotron steepening or a modified spinning dust model improves the fit. This component may account for up to 14% of the total flux at Ka-band (33 GHz). We find no evidence for foreground contamination of the CMB temperature map in the 85% of the sky used for cosmological analysis. 
B. Gold, C. L. Bennett, R. S. Hill, G. Hinshaw, N. Odegard, L. Page,   D. N. Spergel, J. L. Weiland, J. Dunkley, M. Halpern,...