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arXiv · astro-ph/0312459

Three Lyman-alpha Emitters at z approx 6: Early GMOS/Gemini Data from the GLARE Project

Elizabeth R. Stanway·Karl Glazebrook·Andrew J. Bunker·Roberto G. Abraham·Isobel Hook·James Rhoads·Patrick J. McCarthy·Brian Boyle·Matthew Colless·David Crampton·Warrick Couch·Inger Jørgensen·Sangeeta Malhotra·Rick Murowinski·Kathy Roth·Sandra Savaglio·Zlatan Tsvetanov
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Abstract

We report spectroscopic detection of three z~6 Lyman-alpha emitting galaxies, in the vicinity of the Hubble Ultra Deep Field, from the early data of the Gemini Lyman-$α$ at Reionisation Era (GLARE) project. Two objects, GLARE#3001 (z =5.79) and GLARE#3011 (z =5.94), are new detections and are fainter in $z'$ (z'_{AB} =26.37 and 27.15) than any Lyman break galaxy previously detected in Lyman-alpha. A third object, GLARE#1042 (z =5.83) has previously been detected in line emission from the ground; we report here a new spectroscopic continuum detection. Gemini/GMOS-S spectra of these objects, obtained using nod & shuffle, are presented together with a discussion of their photometric properties. All three objects were selected for spectroscopy via the i-drop Lyman Break technique, the two new detections from the GOODS v1.0 imaging data. The red i'-z' colors and high equivalent widths of these objects suggest a high-confidence z>5 Lyman-alpha identification of the emission lines. This brings the total number of known z>5 galaxies within 9 arcmin of the Hubble Ultra Deep Field to four, of which three are at the same redshift (z=5.8 within 2000 km/s suggesting the existence of a large-scale structure at this redshift.

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Elizabeth R. Stanway, Karl Glazebrook, Andrew J. Bunker, Roberto G. Abraham, Isobel Hook, James Rhoads, Patrick J. McCarthy, Brian Boyle, Matthew Colless, David Crampton, Warrick Couch, Inger Jørgensen, Sangeeta Malhotra, Rick Murowinski, Kathy Roth, Sandra Savaglio, Zlatan Tsvetanov. 2004-03-05. Three Lyman-alpha Emitters at z approx 6: Early GMOS/Gemini Data from the GLARE Project. https://doi.org/10.1086/383523

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