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تسجيل مستخدم جديدPreliminary Target Selection for the DESI Emission Line Galaxy (ELG) Sample
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DESI will precisely constrain cosmic expansion and the growth of structure by collecting $sim$35 million redshifts across $sim$80% of cosmic history and one third of the sky to study Baryon Acoustic Oscillations (BAO) and Redshift Space Distortions (RSD). We present a preliminary target selection for an Emission Line Galaxy (ELG) sample, which will comprise about half of all DESI tracers. The selection consists of a $g$-band magnitude cut and a $(g-r)$ vs. $(r-z)$ color box, which we validate using HSC/PDR2 photometric redshifts and DEEP2 spectroscopy. The ELG target density should be $sim$2400 deg$^{-2}$, with $sim$65% of ELG redshifts reliably within a redshift range of $0.6<z<1.6$. ELG targeting for DESI will be finalized during a `Survey Validation phase.
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