Foreground analysis from the 1-year Wilkinson Microwave Anisotropy Probe (WMAP) data
Abstract
We present a detailed analysis on the phases of the WMAP foregrounds (synchrotron, free-free and dust emission) of the WMAP K-W bands in order to estimate the significance of the variation of the spectral indices at different components. We first extract the spectral-index varying signals by assuming that the invariant part among different frequency bands have 100% cross-correlation of phases. We then use the minimization of variance, which is normally used for extracting the CMB signals, to extract the frequency independent signals. Such a common signal in each foreground component could play a significant role for any kind of component separation methods, because the methods cannot discriminate frequency independent foregrounds and CMB.
Keywords
Cite
@article{arxiv.astro-ph/0405523,
title = {Foreground analysis from the 1-year Wilkinson Microwave Anisotropy Probe (WMAP) data},
author = {Pavel D. Naselsky and Oleg V. Verkhodanov and Lung-Yih Chiang and Igor D. Novikov},
journal= {arXiv preprint arXiv:astro-ph/0405523},
year = {2009}
}
Comments
For high-resolution paper see http://www.nbi.dk/~chiang/wmap.html In the revised version we add a new section for cross correlation of phases between the derived CMB and the spectral index varying signal