Preliminary Target Selection for the DESI Emission Line Galaxy (ELG)
  Sample
  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.
