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arXiv · 1903.07573

Galaxies of the $z \sim 2$ Universe. I. Grism-Selected Rest-Frame Optical Emission Line Galaxies

William P. Bowman·Gregory R. Zeimann·Robin Ciardullo·Caryl Gronwall·Donald P. Schneider·Adam P. McCarron·Laurel H. Weiss·Guang Yang·Alex Hagen
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Abstract

Euclid, WFIRST, and HETDEX will make emission-line selected galaxies the largest observed constituent in the $z > 1$ universe. However, we only have a limited understanding of the physical properties of galaxies selected via their Ly$\alpha$ or rest-frame optical emission lines. To begin addressing this problem, we present the basic properties of $\sim 2,000$ AEGIS, COSMOS, GOODS-N, GOODS-S, and UDS galaxies identified in the redshift range $1.90 < z < 2.35$ via their [O II], H$\beta$, and [O III] emission lines. For these $z \sim 2$ galaxies, [O III] is generally much brighter than [O II] and H$\beta$, with typical rest-frame equivalent widths of several hundred Angstroms. Moreover, these strong emission-line systems span an extremely wide range of stellar mass ($\sim 3$ dex), star-formation rate ($\sim 2$ dex), and [O III] luminosity ($\sim 2$ dex). Comparing the distributions of these properties to those of continuum selected galaxies, we find that emission-line galaxies have systematically lower stellar masses and lower optical/UV dust attenuations. These measurements lay the groundwork for an extensive comparison between these rest-frame optical emission-line galaxies and Ly$\alpha$ emitters identified in the HETDEX survey.

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William P. Bowman, Gregory R. Zeimann, Robin Ciardullo, Caryl Gronwall, Donald P. Schneider, Adam P. McCarron, Laurel H. Weiss, Guang Yang, Alex Hagen. 2019-03-18. Galaxies of the $z \sim 2$ Universe. I. Grism-Selected Rest-Frame Optical Emission Line Galaxies. https://doi.org/10.3847/1538-4357/ab108a

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