This epoch marked the last major change as the universe in the early cosmos's makeup. 30 % seem not before this study like a significant number. Such stars have been thousands and hundreds have spewed into the elements into space. Modern stars inhabit mostly younger parts and the spiral arms. Radio astronomy is entering rapidly a period of significant computational challenges. The key open questions require fast all-sky survey capabilities and high sensitivity from modern telescopes. Moore's Law is driving also in the data aquisition stream digitization to the individual antenna receptors.
Image formation is a complex, multi-step numerical procedure. New users of radio-astronomical telescopes is a particular impediment to smaller institutions. Current data demand high-performance automated pipeline reduction. The Precision Array is a low-frequency radio interferometer uses. Funding provided in partnership by the National Science Foundation. Modern cosmology predicts the existence of a mostly neutral intergalactic medium. The 21cm hyperfine transition of neutral hydrogen provides a unique tracer of the primordial IGM. The direct observation of the neutral IGM be an achievement with the discovery of the Cosmic Microwave Background. PAPER is a focused experiment, a Phase-I HERA activity. PAPER activities began with the deployment of a 4-antenna in 2005. This new system incorporated antenna elements with a digital correlator and ground-screen flaps. Deployments began with the deployment and ground breaking. Astrophysics Decadal Survey report and The Astronomy emphasized a consensus that the most incisive probe of cosmic reionization in the US astronomy community.