Analysis of WMAP 7-year Temperature Data: Astrophysics of the Galactic Haze
Abstract
We analyse WMAP 7-year temperature data, jointly modeling the cosmic microwave background (CMB) and Galactic foreground emission. We use the Commander code based on Gibbs sampling. Thus, from the WMAP7 data, we derive simultaneously the CMB and Galactic components on scales larger than 1deg with sensitivity improved relative to previous work. We conduct a detailed study of the low-frequency foreground with particular focus on the "microwave haze" emission around the Galactic center. We demonstrate improved performance in quantifying the diffuse galactic emission when Haslam 408MHz data are included together with WMAP7, and the spinning and thermal dust emission is modeled jointly. We also address the question of whether the hypothetical galactic haze can be explained by a spatial variation of the synchrotron spectral index. The excess of emission around the Galactic center appears stable with respect to variations of the foreground model that we study. Our results demonstrate that the new galactic foreground component - the microwave haze - is indeed present.
Keywords
Cite
@article{arxiv.1110.5418,
title = {Analysis of WMAP 7-year Temperature Data: Astrophysics of the Galactic Haze},
author = {Davide Pietrobon and Krzysztof M. Gorski and James Bartlett and Anthony J. Banday and Gregory Dobler and Loris P. L. Colombo and Luca Pagano and Graca Rocha and Rajib Saha and Jeffrey B. Jewell and Sergi R. Hildebrandt and Hans Kristian Eriksen and Charles R. Lawrence},
journal= {arXiv preprint arXiv:1110.5418},
year = {2012}
}
Comments
16 pages, 16 figures, Published on ApJ