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تسجيل مستخدم جديدThe $z sim 2$ $rm{[O III]}$ Luminosity Function of Grism-selected Emission-line Galaxies
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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 these programs relies upon knowing the number of galaxies that will be found and the bias of the galaxy population. Here we measure the $rm{[O III]} lambda 5007$ luminosity function for a vetted sample of 1951 $m_{rm J+JH+H} < 26$ galaxies with unambiguous redshifts between $1.90 < z < 2.35$, which were selected using HST/WFC3 G141 grism frames made available by the 3D-HST program. These systems are directly analogous to the galaxies that will be identified by the Euclid and Roman missions, which will utilize grism spectroscopy to find $rm{[O III]} lambda 5007$-emitting galaxies at $0.8 lesssim z lesssim 2.7$ and $1.7 lesssim z lesssim 2.8$, respectively. We interpret our results in the context of the expected number counts for these upcoming missions. Finally, we combine our dust-corrected $rm{[O III]}$ luminosities with rest-frame ultraviolet star formation rates to present the first estimate of the SFR density associated with $1.90 < z < 2.35$ $rm{[O III]}$-emitting galaxies. We find that these grism-selected galaxies contain roughly half of the total star formation activity at $zsim2$.
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