Searching for star formation beyond reionization

Abstract

The goal of searching back in cosmic time to find star formation during the epoch of reionization will soon be within reach. We assess the detectability of high-redshift galaxies by combining cosmological hydrodynamic simulations of galaxy formation, stellar evolution models appropriate for the first generations of stars, and estimates of the efficiency for Lyalpha to escape from forming galaxies into the intergalactic medium. Our simulated observations show that Lyalpha emission at z similar to 8 may be observable in the near-infrared with 8 m class telescopes and present-day technology. Not only is the detection of early star-forming objects vital to understanding the underlying cause of the reionization of the universe, but the timely discovery of a star-forming population - or even an z 1 7 interesting upper limit on the emergent flux from these objects - will have implications for the design of the next generation of ground- and space-based facilities.