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arXiv · 0803.0715

Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Galactic Foreground Emission

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. Jarosik·A. Kogut·E. Komatsu·D. Larson·S. S. Meyer·M. R. Nolta·E. Wollack·E. L. Wright
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Abstract

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.

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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. Jarosik, A. Kogut, E. Komatsu, D. Larson, S. S. Meyer, M. R. Nolta, E. Wollack, E. L. Wright. 2008-03-05. Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Galactic Foreground Emission. https://doi.org/10.1088/0067-0049/180/2/265

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