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arXiv · 0807.1890

The DEEP2 Redshift Survey: Lyman Alpha Emitters in the Spectroscopic Database

Marcin Sawicki·Brian C. Lemaux·Puragra Guhathakurta·Evan N. Kirby·Nicholas P. Konidaris·Crystal L. Martin·Michael C. Cooper·David C. Koo·Jeffrey A. Newman·Benjamin J. Weiner
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Abstract

We present the first results of a search for Lyman-alpha emitters (LAEs) in the DEEP2 spectroscopic database that uses a search technique that is different from but complementary to traditional narrowband imaging surveys. We have visually inspected ~20% of the available DEEP2 spectroscopic data and have found nine high-quality LAEs with clearly asymmetric line profiles and an additional ten objects of lower quality, some of which may also be LAEs. Our survey is most sensitive to LAEs at z=4.4-4.9 and that is indeed where all but one of our high-quality objects are found. We find the number density of our spectroscopically-discovered LAEs to be consistent with those found in narrowband imaging searches. The combined, averaged spectrum of our nine high-quality objects is well fit by a two-component model, with a second, lower-amplitude component redshifted by ~420 km/s with respect to the primary Lyman-alpha line, consistent with large-scale outflows from these objects. We conclude by discussing the advantages and future prospects of blank-sky spectroscopic surveys for high-z LAEs.

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Marcin Sawicki, Brian C. Lemaux, Puragra Guhathakurta, Evan N. Kirby, Nicholas P. Konidaris, Crystal L. Martin, Michael C. Cooper, David C. Koo, Jeffrey A. Newman, Benjamin J. Weiner. 2008-07-11. The DEEP2 Redshift Survey: Lyman Alpha Emitters in the Spectroscopic Database. https://doi.org/10.1086/591779

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