Ravi Subrahmanyan (S&A, CSIRO)

Abstract: As First Light from the first stars transforms the universe from the dark ages into cosmic dawn, the history may be traced in redshifted 21-cm from neutral hydrogen in the gas. Efforts to build precision radiometers over the 40-200 MHz band to detect this faint signal are beginning to yield results of significance to the theory, thus constraining the starlight of the earliest galaxies. I will present the progression in SARAS radiometers that have been deployed in remote sites in India – at the Timbaktu collective, in the trans-Himalayan plateau and, most recently, floated on a remote lake. I will then discuss the impact of the data on the astrophysics of the Epoch of Reionisation and Cosmic Dawn, our attempt to confirm the EDGES detection, and the road ahead.