论文标题
Megaparsec-Scale结构周围的原始群集核心SPT2349 $ - $ 56 $ z \，{=} \，4.3 $，4.3 $
Megaparsec-scale structure around the proto-cluster core SPT2349$-$56 at $z\,{=}\,4.3$
论文作者
论文摘要
我们提出了$ z \，{=} \，4.3 $结构SPT2349 $ - $ 56的广泛的ALMA光谱后续程序，这是已知的最积极的恒星原始群集之一，以使用其[C {\ sc II}] 158 \，$ m $ m和mboble和\ mbox（co（4），以识别其其他成员。 In addition to robustly detecting the 14 previously published galaxies in this structure, we identify a further 15 associated galaxies at $z\,{=}\,4.3$, resolving 55$\,{\pm}\,$5\,per cent of the 870-$μ$m flux density at 0.5\,arcsec resolution compared to 21\,arcsec single-dish data.这些星系分布在一个中央芯中，其中包含23个星系，直径为300 \，KPC，北部延伸延伸，从核心偏移了400 \ kpc，其中包含三个星系。我们从主要结构中发现了红色{\ it Herschel \/}的另外三个星系 - 尖峰源1.5 \，MPC，这表明与SPT2349 $ -56相同的红移存在许多其他来源，这些源尚未在我们数据的有限覆盖范围中检测到。 An analysis of the velocity distribution of the central galaxies indicates that this region may be virialized with a mass of (9$\pm$5)$\,{\times}\,$10$^{12}$\,M$_{\odot}$, while the two offset galaxy groups are about 30 and 60\,per cent less massive and show significant velocity offsets from the central group.我们计算[C {\ sc ii}]和远红外数量计数，并找到[C {\ sc ii}]发光函数中断裂的证据。我们估计SPT2349 $ - $ 56的平均SFR密度，其中包含单端发射（合适的直径为720 \，kpc），假设球形对称性是大致的4 $ \，{\ times} \，10^4 $ \，m $ _ {\ odot} $ \，yr $^{ - 1} $ \，mpc $^{ - 3} $;这可能比模拟中最极端的例子大的数量级。
We present an extensive ALMA spectroscopic follow-up programme of the $z\,{=}\,4.3$ structure SPT2349$-$56, one of the most actively star-forming proto-cluster cores known, to identify additional members using their [C{\sc ii}] 158\,$μ$m and \mbox{CO(4--3)} lines. In addition to robustly detecting the 14 previously published galaxies in this structure, we identify a further 15 associated galaxies at $z\,{=}\,4.3$, resolving 55$\,{\pm}\,$5\,per cent of the 870-$μ$m flux density at 0.5\,arcsec resolution compared to 21\,arcsec single-dish data. These galaxies are distributed into a central core containing 23 galaxies extending out to 300\,kpc in diameter, and a northern extension, offset from the core by 400\,kpc, containing three galaxies. We discovered three additional galaxies in a red {\it Herschel\/}-SPIRE source 1.5\,Mpc from the main structure, suggesting the existence of many other sources at the same redshift as SPT2349$-$56 that are not yet detected in the limited coverage of our data. An analysis of the velocity distribution of the central galaxies indicates that this region may be virialized with a mass of (9$\pm$5)$\,{\times}\,$10$^{12}$\,M$_{\odot}$, while the two offset galaxy groups are about 30 and 60\,per cent less massive and show significant velocity offsets from the central group. We calculate the [C{\sc ii}] and far-infrared number counts, and find evidence for a break in the [C{\sc ii}] luminosity function. We estimate the average SFR density within the region of SPT2349$-$56 containing single-dish emission (a proper diametre of 720\,kpc), assuming spherical symmetry, to be roughly 4$\,{\times}\,10^4$\,M$_{\odot}$\,yr$^{-1}$\,Mpc$^{-3}$; this may be an order of magnitude greater than the most extreme examples seen in simulations.
