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arXiv · 2208.01660

Stellar Populations of Lyman-alpha Emitting Galaxies in the HETDEX Survey I: An Analysis of LAEs in the GOODS-N Field

Adam P. McCarron·Steven L. Finkelstein·Oscar A. Chavez Ortiz·Dustin Davis·Erin Mentuch Cooper·Intae Jung·Delaney R. White·Gene C. K. Leung·Karl Gebhardt·Viviana Acquaviva·William P. Bowman·Robin Ciardullo·Eric Gawiser·Caryl Gronwall·Gary J. Hill·Wolfram Kollatschny·Martin Landriau·Chenxu Liu·Daniel N. Mock·Ariel G. Sanchez
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Abstract

We present the results of a stellar-population analysis of Lyman-alpha 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 Lyman-alpha detections. Using photometric data spanning as many as 11 filters covering 0.4-4.5 microns from the Hubble and Spitzer Space Telescopes, we study the objects' global properties and explore which properties impact the strength of Lyman-alpha emission. We measure a median stellar mass of 0.8 (^+2.9_-0.5) x 10^9 Msol and conclude that the physical properties of HETDEX spectroscopically-selected LAEs are comparable to LAEs selected by previous deep narrow band studies. We find that stellar mass and star formation rate correlate strongly with the Lyman-alpha equivalent width. We then use a known sample of z>7 LAEs to perform a proto-study of predicting Lyman-alpha emission from galaxies in the Epoch of Reionization, finding agreement at the 1-sigma level between prediction and observation for the majority of strong emitters.

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Adam P. McCarron, Steven L. Finkelstein, Oscar A. Chavez Ortiz, Dustin Davis, Erin Mentuch Cooper, Intae Jung, Delaney R. White, Gene C. K. Leung, Karl Gebhardt, Viviana Acquaviva, William P. Bowman, Robin Ciardullo, Eric Gawiser, Caryl Gronwall, Gary J. Hill, Wolfram Kollatschny, Martin Landriau, Chenxu Liu, Daniel N. Mock, Ariel G. Sanchez. 2022-08-02. Stellar Populations of Lyman-alpha Emitting Galaxies in the HETDEX Survey I: An Analysis of LAEs in the GOODS-N Field. https://doi.org/10.3847/1538-4357%2Fac8546

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