Cosmic variance of the 21-cm global signal

  title={Cosmic variance of the 21-cm global signal},
  author={Julian B. Mu{\~n}oz and Francis-Yan Cyr-Racine},
  journal={arXiv: Cosmology and Nongalactic Astrophysics},
Cosmological measurements of the 21-cm line of neutral hydrogen are poised to dramatically enhance our understanding of the early universe. In particular, both the epochs of reionization and cosmic dawn remain largely uncharted, and the 21-cm signal is one of the few probes to reach them. The simplest 21-cm measurement is the global signal (GS), which corresponds to the averaged absorption or emission of 21-cm photons across the entire sky. While bright radio foregrounds swamp the cosmic signal… 

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