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arXiv · 1407.6223

A Consistency Relation for the CMB B-mode Polarization in the Squeezed Limit

A. Kehagias·A. Moradinezhad-Dizgah·J. Noreña·H. Perrier·A. Riotto
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Abstract

A large-scale temperature perturbation has a non-zero correlation with the power spectrum of B-modes of cosmological origin on short scales while the corresponding correlation is expected to be zero for B-modes sourced by galactic foregrounds. We thus compute the squeezed limit of a three-point function in which one correlates the temperature fluctuations at large scales with two polarization modes at small scales. In the particular case of the B-mode polarization we obtain a relation that connects the squeezed limit of the $TBB$ three-point function with the cosmological B-mode power spectrum, which can be used as a consistency relation. This could in principle help to distinguish a primordial signal from that induced by inter-stellar dust.

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A. Kehagias, A. Moradinezhad-Dizgah, J. Noreña, H. Perrier, A. Riotto. 2014-07-23. A Consistency Relation for the CMB B-mode Polarization in the Squeezed Limit. https://doi.org/10.1088/1475-7516%2F2014%2F10%2F011

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