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arXiv · 1802.07432

Enhanced global signal of neutral hydrogen due to excess radiation at cosmic dawn

Chang Feng·Gilbert Holder
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Abstract

We revisit the global 21cm signal calculation incorporating a possible radio background at early times, and find that the global 21cm signal shows a much stronger absorption feature, which could enhance detection prospects for future 21 cm experiments. In light of recent reports of a possible low-frequency excess radio background, we propose that detailed 21 cm calculations should include a possible early radio background.

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Chang Feng, Gilbert Holder. 2018-02-21. Enhanced global signal of neutral hydrogen due to excess radiation at cosmic dawn. https://doi.org/10.3847/2041-8213%2Faac0fe

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