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arXiv · 1806.09625

Constraining the Expansion History and Early Dark Energy with Line Intensity Mapping

Kirit S. Karkare·Simeon Bird
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Abstract

We consider the potential for line intensity mapping (IM) experiments to measure the baryon acoustic oscillations (BAO) from 3 < z < 6. This would constrain the expansion history in a redshift range that is currently unexplored. We calculate the map depths that future IM experiments targeting the CO(1-0) rotational transition line and [CII] ionized carbon fine-structure line would need to achieve in order to measure the BAO. We find that near-future IM experiments could constrain the BAO scale to 5% or better depending on CO/[CII] model amplitude. This measurement is at a precision that could make competitive constraints on models of early dark energy.

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Kirit S. Karkare, Simeon Bird. 2018-06-25. Constraining the Expansion History and Early Dark Energy with Line Intensity Mapping. https://doi.org/10.1103/physrevd.98.043529

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