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arXiv · 1409.0265

Observed parity-odd CMB temperature bispectrum

Maresuke Shiraishi·Michele Liguori·James R. Fergusson
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Abstract

Parity-odd non-Gaussianities create a variety of temperature bispectra in the cosmic microwave background (CMB), defined in the domain: $\ell_1 + \ell_2 + \ell_3 = {\rm odd}$. These models are yet unconstrained in the literature, that so far focused exclusively on the more common parity-even scenarios. In this work, we provide the first experimental constraints on parity-odd bispectrum signals in WMAP 9-year temperature data, using a separable modal parity-odd estimator. Comparing theoretical bispectrum templates to the observed bispectrum, we place constraints on the so-called nonlineality parameters of parity-odd tensor non-Gaussianities predicted by several Early Universe models. Our technique also generates a model-independent, smoothed reconstruction of the bispectrum of the data for parity-odd configurations.

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Maresuke Shiraishi, Michele Liguori, James R. Fergusson. 2015-01-08. Observed parity-odd CMB temperature bispectrum. https://doi.org/10.1088/1475-7516%2F2015%2F01%2F007

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