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arXiv · 1403.4222

General parity-odd CMB bispectrum estimation

Maresuke Shiraishi·Michele Liguori·James R. Fergusson
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Abstract

We develop a methodology for estimating parity-odd bispectra in the cosmic microwave background (CMB). This is achieved through the extension of the original separable modal methodology to parity-odd bispectrum domains ($\ell_1 + \ell_2 + \ell_3 = {\rm odd}$). Through numerical tests of the parity-odd modal decomposition with some theoretical bispectrum templates, we verify that the parity-odd modal methodology can successfully reproduce the CMB bispectrum, without numerical instabilities. We also present simulated non-Gaussian maps produced by modal-decomposed parity-odd bispectra, and show the consistency with the exact results. Our new methodology is applicable to all types of parity-odd temperature and polarization bispectra.

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Maresuke Shiraishi, Michele Liguori, James R. Fergusson. 2014-05-08. General parity-odd CMB bispectrum estimation. https://doi.org/10.1088/1475-7516%2F2014%2F05%2F008

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