星系际介质（IGM）被认为包含了宇宙中的大多数重子，并追踪与星系相同的暗物质结构，形成细丝和片。Lya吸收体是IGM中性成分的样品，在低红移和高红移下已被广泛研究，但Lya吸收、星系和大尺度结构之间的确切关系在观测上没有很好的约束。在这项研究中，我们的目标是通过使用来自各种仪器的档案观测数据来表征在退行速度Delta v \leq 6700 km/s时Lya吸收体与附近过密宇宙结构（星系细丝）之间的关系。我们分析了587干预的Lya吸收器的302河外背景源与COS安装在HST的光谱。我们将吸收线信息与最初由Courtois等人（2013年）绘制的五个局部星系细丝的星系数据相结合。沿着靠近灯丝的91条视线，我们识别出215（227）个Lya吸收系统（组件）。其中，74个Lya系统在位置和速度上与星系细丝对齐，表明这些吸收体和星系追踪相同的大尺度结构。顺时针排列的Lya吸收体具有比z=0时的一般Lya群体高约90%的入射率（对于log N HI \geq 13.2，dN/dz=189）和略微较浅的柱密度分布函数斜率（-β = -1.47），反映了细丝的物质过密度。最强的Lya吸收体优先发现在星系附近或靠近灯丝的轴，尽管在这种关系中存在大量的散射。我们的样本的吸收器集群更强烈地围绕灯丝轴比随机分布的样本会做（由KS测试证实），但集群信号是不太明显，比在灯丝的星系。
英文摘要：
The intergalactic medium (IGM) is believed to contain the majority of baryons in the universe and to trace the same dark matter structure as galaxies, forming filaments and sheets. Lya absorbers, which sample the neutral component of the IGM, have been extensively studied at low and high redshift, but the exact relation between Lya absorption, galaxies and the large-scale structure is observationally not well-constrained. In this study, we aim at characterising the relation between Lya absorbers and nearby overdense cosmological structures (galaxy filaments) at recession velocities Delta v \leq 6700 km/s by using archival observational data from various instruments. We analyse 587 intervening Lya absorbers in the spectra of 302 extragalactic background sources obtained with the COS installed on the HST. We combine the absorption-line information with galaxy data of five local galaxy filaments originally mapped by Courtois et al. (2013). Along the 91 sightlines that pass close to a filament, we identify 215 (227) Lya absorption systems (components). Among these, 74 Lya systems are aligned in position and velocity with the galaxy filaments, indicating that these absorbers and the galaxies trace the same large-scale structure. The filament-aligned Lya absorbers have a ~90 percent higher rate of incidence (dN/dz=189 for log N HI \geq 13.2) and a mildly shallower slope (-beta = -1.47) of the column density distribution function than the general Lya population at z=0, reflecting the filaments' matter overdensity. The strongest Lya absorbers are preferentially found near galaxies or close to the axis of a filament, although there is substantial scatter in this relation. Our sample of absorbers clusters more strongly around filament axes than a randomly distributed sample would do (as confirmed by a KS test), but the clustering signal is less pronounced than for the galaxies in the filaments.
HST/COS Observations of the Ly alpha Forest toward the BL Lac Object 1ES1553+113
本文介绍了BL Lac天体1 ES 1553 +113的宇宙起源摄谱仪（HST/COS）在1135-1795波长范围内的新的远紫外光谱。数据显示了一个平滑的连续谱，在ISM和IGM中产生了丰富的窄吸收特征。这些特征包括41个0<z<0.43的Lya吸收体，其中14个在多个莱曼线中检测到，6个在一个或多个金属线中检测到。我们分析了在z=0.188处的Lya吸收剂的富金属三重态，其中检测到OVI、NV和CIII吸收。硅离子（SiIII/IV）未被检测到相当强的上限，并且我们使用测量的SiIII/CIII上限来推导吸收剂络合物的最强组分的丰度极限[C/Si]>0.6。星系红移巡天显示，许多大质量星系的红移与这个吸收复合体大致相同，这表明它产生于大尺度的星系细丝中。1 ES 1553 +113是最亮的河外X射线源和γ射线源之一，是高能天体物理学界的重要研究对象。1 ES 1553 +113没有固有的发射或吸收特性，因此没有直接的红移测定。我们使用介入的Lya吸收体对红移进行直接限制：基于确认的Lya+OVI吸收体的z_em>0.395，基于Lya的单线检测的z_em>0.433。COS/FUV数据仅对z<0.47的Lya吸收体敏感，但我们提出了z_em 0.4的统计参数<0.58 based on the non-detection of any Lyb absorbers at z…
Assessing the dust selection bias in quasar absorbers at 0.7 < z< 1.6: Zn/Fe abundances in a radio-selected sample
完整的光学和无线电吸收线系统（CORALS）调查以前曾被用来证明z>1.6阻尼莱曼α系统的数密度，气体和金属含量在震级有限的调查中没有被显著低估。本文选取了在红移0.7 < z < 1.6范围内光学完全0.7 < z <0.5的Mg Ⅱ强吸收体样品< 1.6 CORALS sample of Ellison et al. is used to assess the potential of dust bias at intermediate redshifts. From echelle spectra of all CORALS absorbers with MgII lambda 2796 and FeII lambda 2600 rest equivalent widths >，测定了Zn、Cr、Fe、Mn和Si的柱密度。的范围内的灰尘，金属比和推断的数密度的DLAs从D-指数是一致的光学样品。我们还报道了在红移范围1.7 < z< 2.0的阶梯光栅数据中发现的4个新吸收体，其中两个是确认的DLA，一个是亚DLA，而第四个Lya线没有被覆盖。
Lyman-alpha Blobs Like Company : The Discovery of A Candidate 100 kpc Lyman-alpha Blob Near to A Radio Galaxy with A Giant Lyman-alpha halo, B3 J2330+3927 at z=3.1
The Gaseous Environment of High-z Galaxies: Precision Measurements of Neutral Hydrogen in the Circumgalactic Medium of z ~ 2-3 Galaxies in the Keck Baryonic Structure Survey
Pinpointing the cosmic web between massive galaxy clusters I. The incidence of HI and OVI as WHIM tracers
Pontificia Universidad Católica de Valparaíso（智利天主教瓦帕莱索大学）；Universidad Técnica Federico Santa María（费德里科·圣塔玛丽亚理工大学）；Leibniz-Institut for Astrophysik Potsdam (AIP)（波茨坦阿基米德天体物理研究所）；The University of Tokyo（东京大学）；University of California, Santa Cruz（加州大学圣克鲁兹分校）；New Mexico State University（新墨西哥州立大学）；University of Edinburgh（爱丁堡大学）；University of Washington（华盛顿大学）；CONICET-Universidad Nacional de Córdoba（阿根廷国家科学研究委员会-科尔多瓦国立大学）
