Understand
We explore the ability of observations of the global brightness temperature of the 21-cm signal to constrain the reionization history and the properties of the ionizing sources.
- In order to describe the reionization signal, we employ either a commonly-used toy model or a structure formation model that parameterizes the properties of the ionizing sources.
- If the structure formation model captures the actual evolution of the reionization signal, then detecting the signal is somewhat easier than it would be for the toy model; using the toy model in this case also leads to systematic errors in reconstructing the reionization history, though a sufficiently sensitive experiment should be able to distinguish between the two models.
- We show that under optimistic assumptions regarding systematic noise and foreground removal, one-year observations of the global 21-cm spectrum should be able to detect a wide range of realistic models and measure the main features of the reionization history while constraining the key properties of the ionizing sources.