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arXiv · 1803.02365

Strong Hydrogen Absorption at Cosmic Dawn: the Signature of a Baryonic Universe

Stacy McGaugh
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Abstract

The recently reported detection of redshifted 21cm absorption at $z \approx 17$ is a significant advance in the exploration of the cosmic dark ages. The observed signal ($T_{\mathrm{21}} \approx -0.5$ K with the limit $T_{\mathrm{21}} < -0.3$ K at 99\% c.l.) is anomalously strong for $Λ$CDM, which predicts at most $-0.24$ K. Here I show that the strong observed signal is expected in a purely baryonic universe.

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Stacy McGaugh. 2018-03-06. Strong Hydrogen Absorption at Cosmic Dawn: the Signature of a Baryonic Universe. https://doi.org/10.3847/2515-5172%2Faab497

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