RSAA Colloquia / Seminars / Feast-of-Facts: Wednesday, 01 March 2017, 11:00-12:00; Duffield Lecture Theatre

Cathryn Trott

"Exploring the Epoch of Reionisation with current and future low-frequency radio telescopes"

I will review efforts being made to detect and explore the neutral hydrogen signal from the first billion years of the universe. Neutral hydrogen acts as a tracer of the growth of structure, and encodes key information about the astrophysical conditions in the intergalactic medium while the first ionising sources illuminated the universe. The spatial distribution and evolution of hydrogen can be used to constrain models of the growth of the first structures, their radiation fields and source type, and physical conditions of the gas medium. Despite this promise of great discovery, detection of the weak cosmological signal is a major challenge for current and future low-frequency radio telescopes. Beyond the simple weakness of the signal, the need to extract information from contaminated data observed through complex instrument, is proving a major hurdle. I will describe the progress we have made with the Murchison Widefield Array, leading to the design of the future SKA-Low, to extract this information, and prospects for the future of EoR science. I will also describe exciting prospects for connecting this information to the low redshift universe, providing a full history of the evolution of structure in the universe.