Redshifted 21 centimeter emission from the pre-reionization era. I. Mean signal and linear fluctuations

  title={Redshifted 21 centimeter emission from the pre-reionization era. I. Mean signal and linear fluctuations},
  author={Nickolay Y. Gnedin and Peter A. Shaver},
  journal={The Astrophysical Journal},
We use cosmological simulations of reionization to predict the possible signal from the redshifted 21 cm line of neutral hydrogen in the pre-reionization era and to investigate the observability of this signal. We show that the separation of the mean (global) signal over the whole sky from the known foreground contamination may be feasible but very challenging. In agreement with previous studies, we demonstrate that measuring angular fluctuations in the H I signal is likely to be extremely… Expand
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