论文标题
环境对蜘蛛网原始群集中星系星系的环境影响的迹象z = 2.16
Signs of environmental effects on star-forming galaxies in the Spiderweb protocluster at z=2.16
论文作者
论文摘要
我们使用VLT/KMO的多对象近红外（NIR）光谱法调查环境在SpiderWeb原始集群中狭窄波段选定的h $α$ emitters（HAES）在$ z = 2.16 $中的离子气体特性的作用。基于REST帧光发射线，H $α$和[NII] $λ$ 6584，我们确认了39个目标的集群成员（即成功率为93％），并测量其星形构型（SFR），气体相氧气丰度和有效的半径。我们通过基于光谱和窄带群集成员的先前样本使用局部和全局密度指标来参数目标驻留在该环境中。我们发现，嵌入在蜘蛛网原始群集中的星形星系与主要序列和形态兼容的星系SFR与$ z = 2.2 $相当的主序列和形态兼容。我们还报告了中级恒星质量的轻度气相金属性增强（$ 0.6 \ pm0.3 $ dex）。此外，我们确定了两个UVJ选择的静态星系，其基于H $α$α$α$的星形形成，并根据其FIR和H $α$排放在一小部分SMG样本中发现极端灰尘遮盖的迹象。有趣的是，这些物体的空间分布与其他HAE的其他不同之处，避免了原始群集核心。最后，我们探索使用CO（1-0）测量的7个星系的气体分数金属图。在气体调节器模型的背景下，我们的对象与相对较低的质量负载因子一致，这表明与宇宙中午处的田间样品相比，流出活动较低，因此暗示了这种大型原始群集中环境效应的开始。
We use multi-object near-infrared (NIR) spectroscopy with VLT/KMOS to investigate the role of the environment in the evolution of the ionized gas properties of narrow-band selected H$α$ emitters (HAEs) in the Spiderweb protocluster at $z=2.16$. Based on rest-frame optical emission lines, H$α$ and [NII]$λ$6584, we confirm the cluster membership of 39 of our targets (i.e. 93% success rate), and measure their star-formation rates (SFR), gas-phase oxygen abundances and effective radius. We parametrize the environment where our targets reside by using local and global density indicators based on previous samples of spectroscopic and narrow-band cluster members. We find that star-forming galaxies embedded in the Spiderweb protocluster display SFRs compatible with those of the main sequence and morphologies comparable to those of late-type galaxies at $z=2.2$ in the field. We also report a mild gas-phase metallicity enhancement ($0.6\pm0.3$ dex) at intermediate stellar masses. Furthermore, we identify two UVJ-selected quiescent galaxies with residual H$α$-based star formation and find signs of extreme dust obscuration in a small sample of SMGs based on their FIR and H$α$ emission. Interestingly, the spatial distribution of these objects differs from the rest of HAEs, avoiding the protocluster core. Finally, we explore the gas fraction-gas metallicity diagram for 7 galaxies with molecular gas masses measured by 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 the cosmic noon and thus, hinting at the onset of environmental effects in this massive protocluster.
