The Radio Background below 100 MHz

  title={The Radio Background below 100 MHz},
  author={Jayce Dowell and Gregory B. Taylor},
  journal={The Astrophysical Journal Letters},
The recent detection of the “cosmic dawn” redshifted 21 cm signal at 78 MHz by the Experiment to Detect the Global EoR Signatures (EDGES) differs significantly from theoretical predictions. In particular, the absorption trough is roughly a factor of two stronger than the most optimistic theoretical models. The early interpretations of the origin of this discrepancy fall into two categories. The first is that there is increased cooling of the gas due to interactions with dark matter, while the… 

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