ZFIRE: Similar Stellar Growth in H$\alpha$-emitting Cluster and Field
  Galaxies at z~2
  We compare galaxy scaling relations as a function of environment at $z\sim2$
with our ZFIRE survey where we have measured H$\alpha$ fluxes for 90
star-forming galaxies selected from a mass-limited
[$\log(M_{\star}/M_{\odot})>9$] sample based on ZFOURGE. The cluster galaxies
(37) are part of a confirmed system at z=2.095 and the field galaxies (53) are
at $1.9<z<2.4$; all are in the COSMOS legacy field. There is no statistical
difference between H$\alpha$-emitting cluster and field populations when
comparing their star formation rate (SFR), stellar mass ($M_{\star}$), galaxy
size ($r_{eff}$), SFR surface density [$\Sigma$(H$\alpha_{star}$)], and stellar
age distributions. The only difference is that at fixed stellar mass, the
H$\alpha$-emitting cluster galaxies are $\log(r_{eff})\sim0.1$ larger than in
the field. Approximately 19% of the H$\alpha$-emitters in the cluster and 26%
in the field are IR-luminous ($L_{IR}>2\times10^{11} L_{\odot}$). Because the
LIRGs in our combined sample are $\sim5$ times more massive than the low-IR
galaxies, their radii are $\sim70$% larger. To track stellar growth, we
separate galaxies into those that lie above, on, and below the H$\alpha$
star-forming main sequence (SFMS) using $\Delta$SFR$(M_{\star})=\pm0.2$ dex.
Galaxies above the SFMS (starbursts) tend to have higher H$\alpha$ SFR surface
densities and younger light-weighted stellar ages compared to galaxies below
the SFMS. Our results indicate that starbursts (+SFMS) in the cluster and field
at $z\sim2$ are growing their stellar cores. Lastly, we compare to the
(SFR-$M_{\star}$) relation from RHAPSODY cluster simulations and find the
predicted slope is nominally consistent with the observations. However, the
predicted cluster SFRs tend to be too low by a factor of $\sim2$ which seems to
be a common problem for simulations across environment.
