This award is for continuation of the development of the Precision Array to Probe the Epoch of Reionization (PAPER). The focus of PAPER is the statistical detection of HI 21-cm signals from the neutral intergalactic medium (IGM) during cosmic reionization, an event corresponding to the transition from a fully neutral IGM to a highly ionized IGM caused by the UV radiation from the first stars and supermassive black holes. Probing this last unexplored phase of cosmic evolution has been called out by the Astro2010 Decade Survey as the primary area with extraordinary discovery potential in the study of cosmic structure formation, and this constitutes the main intellectual impact of this research.
During the previous award period, under AST-0804508 and AST-0804523, PAPER established observing sites with 32 antenna elements at both NRAO Green Bank and in the Karoo Desert of South Africa. The current proposal will expand the SA deployment of PAPER to 128 elements and will support on-going observations and analysis using both the GB and SA deployments.
Broader impacts of the program include advancement of techniques in low frequency radio astronomy, and a strong educational emphasis through training of graduate students and postdocs. The project is a major stepping stone toward a future Hydrogen Epoch of Reionization Array (HERA), as recommended by A2010. PAPER has directed fabrication funds where possible to local small businesses, thus providing economic stimulus in the US. Outreach activities have included a number of public talks on the project by graduate students.