2016ApJ...825L...2A

We perform a kinematic analysis of galaxies at z ∼ 2 in the COSMOS legacy field using near-infrared (NIR) spectroscopy from Keck/MOSFIRE as part of the ZFIRE survey. Our sample consists of 75 Ks-band selected star-forming galaxies from the ZFOURGE survey with stellar masses ranging from log(M_*/M_☉)=9.0-11.0, 28 of which are members of a known overdensity at z=2.095. We measure Hα emission-line integrated velocity dispersions (σ_int) from 50 to 230 km/s, consistent with other emission-line studies of z ∼ 2 field galaxies. From these data we estimate virial, stellar, and gas masses and derive correlations between these properties for cluster and field galaxies at z ∼ 2. We find evidence that baryons dominate within the central effective radius. However, we find no statistically significant differences between the cluster and the field, and conclude that the kinematics of star-forming galaxies at z ∼ 2 are not significantly different between the cluster and field environments.