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Foreground analysis from the 1-year Wilkinson Microwave Anisotropy Probe (WMAP) data

Pavel D. Naselsky·Oleg V. Verkhodanov·Lung-Yih Chiang·Igor D. Novikov
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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.

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Pavel D. Naselsky, Oleg V. Verkhodanov, Lung-Yih Chiang, Igor D. Novikov. 2004-07-19. Foreground analysis from the 1-year Wilkinson Microwave Anisotropy Probe (WMAP) data. https://doi.org/10.1142/s0218271805007280

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