Oral Presentation
Gas-phase environmental effects in the Spiderweb protocluster at z=2.16
Presenter: Jose Manuel Perez-martinez (Tohoku University)
We use multi-object near-IR spectroscopy with VLT/KMOS to investigate the role of the environment in the evolution of the gas properties of galaxies in the Spiderweb protocluster at z=2.16. Based on rest-frame optical emission lines, [NII]λ6584 and Hα, we measure star formation rates (SFR) and gas-phase oxygen abundances of 39 protocluster members as a function of local density and global environment properties. Our results show that galaxies embedded in this structure display SFRs compatible with those of the Main Sequence of galaxies, and enhanced metallicity values (0.1-0.2 dex) compared to their coeval field counterparts. Furthermore, we explore the gas fraction-gas metallicity diagram for a few galaxies with molecular gas masses measured by VLA/ATCA using CO(1-0). In the context of the gas-regulator model, our objects are consistent with relatively low mass loading factors, suggesting lower outflow activity than field samples at similar redshift and thus, hinting at the onset of environmental effects in this massive protocluster. We discuss the implications of these results on different scenarios of environmentally driven galaxy evolution during the early stages of massive cluster assembly.
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