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arXiv · 1109.0009

Search for z~6.96 Ly-alpha emitters with Magellan/IMACS in the COSMOS field

Pascale Hibon·Sangeeta Malhotra·James E. Rhoads·Christopher Willott
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Abstract

We report a search for z~6.96 Ly-alpha emitters (LAEs) using a Narrow-Band filter, centered at 9680 Angstroms, with the IMACS instrument on the Magellan telescope at Las Campanas Observatory. We obtain a sample of 6 Ly-alpha emitter candidates of luminosity ~10^42 erg/s in a total area of 465 square arcmin corresponding to a comoving volume of ~ 72000 Mpc^3. From this result, we derive a Ly-alpha luminosity function (LF) at z~6.96 and compare our sample with the only z~6.96 Ly-alpha emitter spectroscopically confirmed to date (Iye et al. 2006). We find no evolution between the z=5.7 and z~7 Ly-alpha luminosity functions, if a majority of our candidates are confirmed. Spectroscopic confirmation for this sample will enable more robust conclusions.

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Pascale Hibon, Sangeeta Malhotra, James E. Rhoads, Christopher Willott. 2011-08-31. Search for z~6.96 Ly-alpha emitters with Magellan/IMACS in the COSMOS field. https://doi.org/10.1088/0004-637x/741/2/101

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