论文标题
z = 2.16的普朗克式尘土飞扬的原始群集与强大的大量H $α$发射星系相关
A Planck-selected dusty proto-cluster at z=2.16 associated with a strong over-density of massive H$α$ emitting galaxies
论文作者
论文摘要
我们通过与Subaru/Moirirs的窄带成像观察发现了与Planck紧凑型源（PHZG237.0+42.5）相关的H-α发射星系的过度密度。 Z = 2.16处的Planck选择的尘土飞扬的原始簇具有38个H-α发射器，其中包括观察到的Moirirs 4'x7'磁场中的六个光谱确认的星系（对应于〜2.0x3.5〜mpc^2的物理尺度）。我们发现，具有log（m*/msun）> 10.5的大量H-alpha发射器被强烈聚集在原始群集的核心中（从H-Alpha发射器的密度峰内〜300-KPC内）。该原始群集中的大多数H-Alpha发射器都使用基于H-Alpha的SFR估计值沿着星形成主序列，而通过集成基于H-Alpha的SFR的群集得出的SFR群集是比Planck/Herschel Fir Fir Phodmotery估算的量度小的级数。我们的结果表明，H-Alpha是一种很好的观察，用于检测适度的星形星系并追踪高Z尘土飞扬的原始群体中及其周围的大规模环境，但是在H-Alpha观察中，有很大一部分的恒星形成可能会被粉尘掩盖并未被发现。
We discovered an over-density of H-alpha-emitting galaxies associated with a Planck compact source in the COSMOS field (PHzG237.0+42.5) through narrow-band imaging observations with Subaru/MOIRCS. This Planck-selected dusty proto-cluster at z=2.16 has 38 H-alpha emitters including six spectroscopically confirmed galaxies in the observed MOIRCS 4'x7' field (corresponding to ~2.0x3.5~Mpc^2 in physical scale). We find that massive H-alpha emitters with log(M*/Msun)>10.5 are strongly clustered in the core of the proto-cluster (within ~300-kpc from the density peak of the H-alpha emitters). Most of the H-alpha emitters in this proto-cluster lie along the star-forming main sequence using H-alpha-based SFR estimates, whilst the cluster total SFR derived by integrating the H-alpha-based SFRs is an order of magnitude smaller than those estimated from Planck/Herschel FIR photometry. Our results suggest that H-alpha is a good observable for detecting moderately star-forming galaxies and tracing the large-scale environment in and around high-z dusty proto-clusters, but there is a possibility that a large fraction of star formation could be obscured by dust and undetected in H-alpha observations.
