Talk page
Title:
Low Frequency Radio Astronomy from the Ends of the Earth
Speaker:
Abstract:
Redshifted 21cm emission from neutral hydrogen is rapidly becoming one of our most powerful observables in cosmology. With it, we can study the evolution of dark energy at low/intermediate redshifts, the epoch of reionization, the first stars in the universe during cosmic dawn, and hopefully one day the cosmic dark ages. Unfortunately at higher redshifts, human-generated interference is a major barrier to 21cm studies (see: https://xkcd.com/2226/). To avoid this interference, we have set up radio telescopes in some of the most remote places on Earth, from the Canadian high Arctic to the sub-Antarctic. I will review the physics of the high-redshift 21cm emission history, discuss the current state of cosmic dawn measurements, and describe some of our current efforts to probe cosfic dawn, and to begin opening a window on the very low-frequency (<10 MHz) sky, which is currently almost completely unexplored.
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