SARAS 2 Constraints on Global 21 cm Signals from the Epoch of Reionization<sup>*</sup>
SARAS 2 Constraints on Global 21 cm Signals from the Epoch of Reionization<sup>*</sup>
Spectral distortions in the cosmic microwave background over the 40--200~MHz band are imprinted by neutral hydrogen in the intergalactic medium prior to the end of reionization. This signal, produced in the redshift range $z = 6-34$ at the rest frame wavelength of 21 cm, has not been detected yet; and …