Searching for Star Formation Beyond Reionization

University Of California-Irvine, Irvine CA

Investigators

Abstract

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Dr Barton will undertake a ground-based search for Lyman-alpha emission from young galaxies seen less than a billion years after the Big Bang, that cosmic expansion has shifted into the near-infrared at 1.2 microns. The search will use filters with a sufficiently narrow bandpass to fit into the dark region between the strong night-sky lines. Dr Barton and her collaborators will survey 30 nearby galaxy clusters using a tunable filter being designed for the near-infrared imaging spectrograph on the Gemini South telescope. The advantage of using clusters is that the gravitational bending of light magnifies and brightens the images of galaxies behind the cluster. For each cluster, this effect should be strong enough in a zone of about 6 square arcseconds to magnify distant galaxies at least 20 times. The PI will also lead two surveys with a new infrared imaging spectrograph at the Keck Observatory, using a narrow-band filter to select Lyman-alpha emission from young galaxies. She will make a deep survey of a single field 6 arcmin across; a shallower survey of 68 fields will cover 2400 square arcminutes. Dr Barton and her team will use models of galaxy formation and evolution to interpret what the results tell us about these young galaxies, and about the ionizing radiation field and the intergalactic gas around them. A graduate student will be trained by participating in the research. The new narrow-band data will be released to the astronomical community. Dr Barton will continue to teach in a summer astronomy program for high school students at UC Irvine. She will also take an active role in the development of the next generation of instrumentation, and in design studies for the planned Thirty Meter Telescope.