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تسجيل مستخدم جديدGalaxies of the $z sim 2$ Universe. I. Grism-Selected Rest-Frame Optical Emission Line Galaxies
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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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Upcoming missions such as Euclid and the Nancy Grace Roman Space Telescope (Roman) will use emission-line selected galaxies to address a variety of questions in cosmology and galaxy evolution in the $z>1$ universe. The optimal observing strategy for
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