论文标题
解密Lyman $α$ blob 1带有深缪斯观测
Deciphering Lyman $α$ blob 1 with deep MUSE observations
论文作者
论文摘要
上下文：Lyman $α$ BLOBS（实验室）是大规模的放射Quiet Lyman $α$（LY $α$）星云，在高密度的原始群集区域中主要发生。尤其是$ z = 3.1 $的原型SSA22A-LAB1已成为电磁频谱中实验室的观察参考。 目的：我们想了解推动实验室的动力机制，以在高$ z $的罕见茂密环境中获得对星系形成过程的经验见解。 方法：使用VLT/Muse Integrallib场光谱仪观察到17.5h的实验室1。我们制作了最佳提取的窄带图像，其中$α$ $ \ lambda1216 $和heii $ \ lambda1640 $。通过使用基于力矩的分析，我们映射了斑点的运动学。 结果：我们检测到$ 10^{ - 19} $ erg s $^{ - 1} $ cm $ $^{ - 2} $ arcsec $^{ - 2} $的$ 10^{ - 19} $ erg s $^{ - 1} $ 10^{ - 19} $ 10^{ - 19} $ 10^{ - 2} $。在这个深度上，我们揭示了实验室1与其北部邻居实验室8之间的桥梁，以及一个向实验室1的南部的壳样细丝。我们发现了一个连贯的大型东西范围的东西$ \ sim $ \ sim $ 1000 km s $^{ - 1} $速度梯度，始终与Blob的主要轴心固定。我们在三个不同的区域中检测到HEII排放，但我们只能为CIV提供上限。 结论：实验室1：电离辐射和反馈效应在嵌入式星系附近占主导地位，而Ly $α$散射在更大的距离中造成了贡献。但是，HEII/LY $α$比率与CIV/LY $α$上的上限相结合，无法区分Agn电离和反馈驱动的冲击。与形态主轴平行的角动量向量的对齐与高质量光环的预测规范似乎是不合时宜的，但很可能反映了实验室\，1位于宇宙网的多个相交细丝的节点上。 （简略）
Context: Lyman $α$ blobs (LABs) are large-scale radio-quiet Lyman $α$ (Ly$α$) nebula at high-$z$ that occur predominantly in overdense proto-cluster regions. Especially the prototypical SSA22a-LAB1 at $z=3.1$ has become an observational reference for LABs across the electromagnetic spectrum. Aims: We want to understand the powering mechanisms that drive the LAB to gain empirical insights into galaxy formation processes within a rare dense environment at high-$z$. Methods: LAB 1 was observed for 17.5h with the VLT/MUSE integral-field spectrograph. We produced optimally extracted narrow band images in Ly$α$ $\lambda1216$ and HeII $\lambda1640$. By using a moment based analysis we mapped the kinematics of the blob. Results: We detect Ly$α$ emission to surface-brightness limits of $10^{-19}$erg s$^{-1}$cm$^{-2}$arcsec$^{-2}$. At this depth we reveal a bridge between LAB 1 and its northern neighbour LAB 8, as well as a shell-like filament towards the south of LAB 1. We find a coherent large scale east-west $\sim$1000 km s$^{-1}$ velocity gradient that is aligned perpendicular to the major axis of the blob. We detect HeII emission in three distinct regions, but we can only provide upper limits for CIV. Conclusions: Various gas excitation mechanisms are at play in LAB 1: Ionising radiation and feedback effects dominate near the embedded galaxies, while Ly$α$ scattering is contributing at larger distances. However, HeII/Ly$α$ ratios combined with upper limits on CIV/Ly$α$ can not discriminate between AGN ionisation and feedback driven shocks. The alignment of the angular momentum vector parallel to the morphological principal axis appears odds with the predicted norm for high-mass halos, but likely reflects that LAB\,1 resides at a node of multiple intersecting filaments of the cosmic web. (Abridged)
