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arXiv · 2312.02511

Cosmological constraints from the EFT power spectrum and tree-level bispectrum of 21cm intensity maps

Liantsoa F. Randrianjanahary·Dionysios Karagiannis·Roy Maartens
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Abstract

We explore the information content of 21cm intensity maps in redshift space using the 1-loop Effective Field Theory power spectrum model and the bispectrum at tree level. The 21cm signal contains signatures of dark matter, dark energy and the growth of large-scale structure in the Universe. These signatures are typically analyzed via the 2-point correlation function or power spectrum. However, adding the information from the 3-point correlation function or bispectrum will be crucial to exploiting next-generation intensity mapping experiments. The bispectrum could offer a unique opportunity to break key parameter degeneracies that hinder the measurement of cosmological parameters and improve on the precision. We use a Fisher forecast analysis to estimate the constraining power of the HIRAX survey on cosmological parameters, dark energy and modified gravity.

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Liantsoa F. Randrianjanahary, Dionysios Karagiannis, Roy Maartens. 2023-12-05. Cosmological constraints from the EFT power spectrum and tree-level bispectrum of 21cm intensity maps. https://doi.org/10.1016/j.dark.2024.101530

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