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arXiv · 2101.11372

Lensing contribution to the 21cm intensity bispectrum

Rahul Kothari·Roy Maartens
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Abstract

Intensity maps of the 21cm emission line of neutral hydrogen are lensed by intervening large-scale structure, similar to the lensing of the cosmic microwave background temperature map. We extend previous work by calculating the lensing contribution to the full-sky 21cm bispectrum in redshift space. The lensing contribution tends to peak when equal-redshift fluctuations are lensed by a lower redshift fluctuation. At high redshift, lensing effects can become comparable to the contributions from density and redshift-space distortions.

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Rahul Kothari, Roy Maartens. 2021-01-27. Lensing contribution to the 21cm intensity bispectrum. https://doi.org/10.1088/1361-6382%2Fabf1c1

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