Astronomy Tea Talk

In addition to understanding the evolution of the galaxy formation out to high redshift, the ISM of z>~6 galaxies is a crucial element for many important probes of cosmic reionization, such as recently discovered Lyman-break systems in the UDF12 data, the evolution of the Keck-detected Lyman-alpha fraction, and intensity mapping of galactic emission lines with ALMA, which can improve the reliability of 21cm tomography. I will present a new, fully-analytic framework for describing the ISM and molecular cloud properties of reionization epoch galaxies that includes physical processes from an enormous range of distance scales---from the tens of megaparsec regions over which cosmic variance operates to the tens of parsec-sized photo-dissociative regions inside molecular clouds---a span typically beyond the reach of numerical simulations. I will discuss the observational consequences of such a model, in particular, examining whether recent Chandra data can constrain the way gas is transported through the disk and making realistic predictions for detecting carbon emission lines with the JVLA and ALMA. These signatures can help us understand the conditions within the high-redshift ISM in advance of JWST and TMT.