Abstract We present the results of a stellar population analysis of 72 Ly α -emitting galaxies (LAEs) in GOODS-N at 1.9 < z < 3.5 spectroscopically identified by the Hobby−Eberly Telescope Dark Energy Experiment (HETDEX). We provide a method for connecting emission-line detections from the blind spectroscopic survey to imaging counterparts, a crucial tool needed as HETDEX builds a massive database of ∼1 million Ly α detections. Using photometric data spanning as many as 11 filters covering 0.4 < λ ( μ m) < 4.5 from the Hubble Space Telescope and Spitzer Space Telescope, we study the objects’ global properties and explore which properties impact the strength of Ly α emission. We measure a median stellar mass of 0.8 − 0.5 + 2.9 × 10 9 M ⊙ and conclude that the physical properties of HETDEX spectroscopically selected LAEs are comparable to LAEs selected by previous deep narrowband studies. We find that stellar mass and star formation rate correlate strongly with the Ly α equivalent width. We then use a known sample of z > 7 LAEs to perform a protostudy of predicting Ly α emission from galaxies in the epoch of reionization, finding agreement at the 1 σ level between prediction and observation for the majority of strong emitters.
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A Search for Lensed Lyα Emitters within the Early HETDEX Data Set
Abstract The Hobby–Eberly Telescope Dark Energy Experiment (HETDEX) is a large-volume spectroscopic survey without preselection of sources, searching ∼540 deg 2 for Ly α emitting galaxies (LAEs) at 1.9 < z < 3.5. Taking advantage of such a wide-volume survey, we perform a pilot study using early HETDEX data to search for lensed Ly α emitters (LAEs). After performing a proof of concept using a previously known lensed LAE covered by HETDEX, we perform a search for previously unknown lensed LAEs in the HETDEX spectroscopic sample. We present a catalog of 26 potential LAEs lensed by foreground, red, non-star-forming galaxies at z ∼ 0.4–0.7. We estimate the magnification for each candidate system, finding 12 candidates to be within the strong lensing regime (magnification μ > 2). Follow-up observations of these potential lensed LAEs have the potential to confirm their lensed nature and explore these distant galaxies in more detail.
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- PAR ID:
- 10454763
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 940
- Issue:
- 1
- ISSN:
- 0004-637X
- Page Range / eLocation ID:
- 9
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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