Polarized CMB Foregrounds: What do we know and how bad is it?

Clive Dickinson

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arXiv · 1005.2572

Polarized CMB Foregrounds: What do we know and how bad is it?

Clive Dickinson

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Abstract

Polarized foregrounds are going to be a serious challenge for detecting CMB cosmological B-modes. Both diffuse Galactic emission and extragalactic sources contribute significantly to the power spectrum on large angular scales. At low frequencies, Galactic synchrotron emission will dominate with fractional polarization $\sim 20-40%$ at high latitudes while radio sources can contribute significantly even on large ($\sim 1^{\circ}$) angular scales. Nevertheless, simulations suggest that a detection at the level of $r=0.001$ might be achievable if the foregrounds are not too complex.

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Clive Dickinson. 2010-05-14. Polarized CMB Foregrounds: What do we know and how bad is it?. https://arxiv.org/abs/1005.2572

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