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arXiv · 1011.4075

The Brightest Of Reionizing Galaxies Survey: Design and Preliminary Results

M. Trenti·L. D. Bradley·M. Stiavelli·P. Oesch·T. Treu·R. J. Bouwens·J. M. Shull·J. W. MacKenty·C. M. Carollo·G. D. Illingworth
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Abstract

We present the first results on the search for very bright (M_AB -21) galaxies at redshift z~8 from the Brightest of Reionizing Galaxies (BoRG) survey. BoRG is a Hubble Space Telescope Wide Field Camera 3 pure-parallel survey that is obtaining images on random lines of sight at high Galactic latitudes in four filters (F606W, F098M, F125W, F160W), with integration times optimized to identify galaxies at z>7.5 as F098M-dropouts. We discuss here results from a search area of approximately 130 arcmin^2 over 23 BoRG fields, complemented by six other pure-parallel WFC3 fields with similar filters. This new search area is more than two times wider than previous WFC3 observations at z~8. We identify four F098M-dropout candidates with high statistical confidence (detected at greater than 8sigma confidence in F125W). These sources are among the brightest candidates currently known at z~8 and approximately ten times brighter than the z=8.56 galaxy UDFy-38135539. They thus represent ideal targets for spectroscopic followup observations and could potentially lead to a redshift record, as our color selection includes objects up to z~9. However, the expected contamination rate of our sample is about 30% higher than typical searches for dropout galaxies in legacy fields, such as the GOODS and HUDF, where deeper data and additional optical filters are available to reject contaminants.

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M. Trenti, L. D. Bradley, M. Stiavelli, P. Oesch, T. Treu, R. J. Bouwens, J. M. Shull, J. W. MacKenty, C. M. Carollo, G. D. Illingworth. 2010-12-29. The Brightest Of Reionizing Galaxies Survey: Design and Preliminary Results. https://doi.org/10.1088/2041-8205%2F727%2F2%2Fl39

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