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arXiv · 2203.04861

Diffuse polarized foregrounds from component separation with QUIJOTE-MFI

E. de la Hoz
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Abstract

Polarized component maps in the Northern Sky are derived from the QUIJOTE-MFI wide survey data at 11 and 13 GHz, the WMAP K and Ka bands and all Planck polarized channels using the parametric component separation method B-SeCRET. The addition of QUIJOTE-MFI data significantly improves the uncertainty in the parameter estimation of the low frequency dominant foreground, in particular the estimation of the synchrotron spectral index. We find statistically significant spatial variability across the sky. A power law model of the synchrotron emission provides a good fit of the data outside the galactic plane but fails to track the complexity of this region. Moreover, when we assume a synchrotron model with uniform curvature we find, in the 95% confidence region, a non-zero $c_s$ value. However, there is not sufficient statistical significance to determine which model is favoured.

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E. de la Hoz. 2022-03-09. Diffuse polarized foregrounds from component separation with QUIJOTE-MFI. https://arxiv.org/abs/2203.04861

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