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Title: HETDEX Public Source Catalog 1—Stacking 50,000 Lyman Alpha Emitters ∗
Abstract

We describe the ensemble properties of the 1.9 <z< 3.5 Lyman alpha emitters (LAEs) found in the HETDEX survey’s first public data release, HETDEX Public Source Catalog 1. Stacking the low-resolution (R∼ 800) spectra greatly increases the signal-to-noise ratio (S/N), revealing spectral features otherwise hidden by noise, and we show that the stacked spectrum is representative of an average member of the set. The flux-limited, LyαS/N restricted stack of 50,000 HETDEX LAEs shows the ensemble biweightaveragez∼ 2.6 LAE to be a blue (UV continuum slope ∼ −2.4 andE(B – V)< 0.1), moderately bright (MUV∼ −19.7) star-forming galaxy with strong Lyαemission (logLLyα∼ 42.8 andWλ(Lyα) ∼ 114 Å), and potentially significant leakage of ionizing radiation. The rest-frame UV light is dominated by a young, metal-poor stellar population with an average age of 5–15 Myr and metallicity of 0.2–0.3Z.

 
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NSF-PAR ID:
10458849
Author(s) / Creator(s):
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Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
954
Issue:
2
ISSN:
0004-637X
Format(s):
Medium: X Size: Article No. 209
Size(s):
Article No. 209
Sponsoring Org:
National Science Foundation
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