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arXiv · 1506.06670

Measuring primordial anisotropic correlators with CMB spectral distortions

Maresuke Shiraishi·Michele Liguori·Nicola Bartolo·Sabino Matarrese
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Abstract

We show that inflationary models with broken rotational invariance generate testable off-diagonal signatures in the correlation between the $μ$-type distortion and temperature fluctuations of the cosmic microwave background. More precisely, scenarios with a quadrupolar bispectrum asymmetry, usually generated by fluctuations of primordial vector fields, produce a nonvanishing $μ$-$T$ correlation when $|\ell_1-\ell_2|=2$. Since spectral distortions are sensitive to primordial fluctuations up to very small scales, a cosmic variance limited spectral distortion experiment can detect such effects with a high signal-to-noise ratio.

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Maresuke Shiraishi, Michele Liguori, Nicola Bartolo, Sabino Matarrese. 2015-10-04. Measuring primordial anisotropic correlators with CMB spectral distortions. https://doi.org/10.1103/physrevd.92.083502

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