Tuesday, January 30, 2018, 12:00pm to 1:00pm
"What Can Galaxies Tell Us About The Epoch of Reionization?"
Abstract: Reionization of intergalactic hydrogen in the universe's first billion years was likely driven by the first stars and galaxies. The timeline of reionization thus encodes information about their properties, but it is not well-measured. I will describe ways to use galaxies at our current observational frontiers to constrain reionization. In particular, Lyman-alpha emission from galaxies can be used to probe the reionizing IGM, but requires disentangling physics on pc to Gpc scales. I will introduce a new forward-modeling framework to infer the average IGM neutral fraction from Lyman-alpha observations. I will present our new neutral fraction measurement at z~7, and describe ongoing efforts to explore the reionization epoch with observations of galaxies and future prospects with JWST.