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تسجيل مستخدم جديدZFIRE: The Kinematics of Star-Forming Galaxies as a Function of Environment at z~2
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We perform a kinematic analysis of galaxies at $zsim2$ 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$_{star}$/M$_{odot}$)$=9.0-11.0$, 28 of which are members of a known overdensity at $z=2.095$. We measure H$alpha$ emission-line integrated velocity dispersions ($sigma_{rm int}$) from 50$-$230 km s$^{-1}$, consistent with other emission-line studies of $zsim2$ field galaxies. From these data we estimate virial, stellar, and gas masses and derive correlations between these properties for cluster and field galaxies at $zsim2$. 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 $zsim2$ are not significantly different between the cluster and field environments.
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