Five-Year Wilkinson Microwave Anisotropy Probe WMAP Observations: Galactic Foreground Emission - AstrophysicsReport as inadecuate




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Abstract: We present a new estimate of foreground emission in the WMAP data, using aMarkov chain Monte Carlo MCMC method. The new technique delivers maps of eachforeground component for a variety of foreground models, error estimates of theuncertainty of each foreground component, and provides an overallgoodness-of-fit measurement. The resulting foreground maps are in broadagreement with those from previous techniques used both within thecollaboration 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 reducedchi-squared of 1.14. However, the model does not work well inside the Galacticplane. The addition of either synchrotron steepening or a modified spinningdust model improves the fit. This component may account for up to 14% of thetotal flux at Ka-band 33 GHz. We find no evidence for foregroundcontamination of the CMB temperature map in the 85% of the sky used forcosmological analysis.



Author: B. Gold, C. L. Bennett, R. S. Hill, G. Hinshaw, N. Odegard, L. Page, D. N. Spergel, J. L. Weiland, J. Dunkley, M. Halpern, N. Jar

Source: https://arxiv.org/







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