2015ApJ...811...28T

We spectroscopically survey the galaxy cluster XMM-LSS J02182-05102 (hereafter IRC 0218) using LRIS (optical) and MOSFIRE (near-infrared) on Keck I as part of the ZFIRE survey. IRC 0218 has a narrow redshift range of defined by 33 members of which 20 are at R Mpc. The cluster redshift and velocity dispersion are and km/s. We reach NIR line sensitivities of ∼0.3x10^–17 erg/s/cm2 that, combined with multi-wavelength photometry, provide extinction-corrected Hα star formation rates (SFR), gas phase metallicities from [N ii]/Hα, and stellar masses. We measure an integrated Hα SFR of ∼325 (26 members; R Mpc) and show that the elevated star formation in the cluster core (R Mpc) is driven by the concentration of star-forming members, but the average SFR per Hα-detected galaxy is half that of members at R ∼ 1 Mpc. However, we do not detect any environmental imprint when comparing attenuation and gas phase metallicities: the cluster galaxies show similar trends with as to the field, e.g., more massive galaxies have larger stellar attenuation. IRC 0218's gas phase metallicity- relation (MZR) is offset to lower metallicities relative to and has a slope of 0.13±0.10. Comparing the MZR in IRC 0218 to the COSMOS cluster at z = 2.1 shows no evolution ( Gyr): the MZR for both galaxy clusters are remarkably consistent with each other and virtually identical to several field surveys at.