论文标题
高红移的观察$α$发射器
Observations of Ly$α$ Emitters at High Redshift
论文作者
论文摘要
在这一系列的讲座中，我回顾了我们对高$ z $ $ $α$发射器（LAES）和相关科学主题的观察理解。自1990年代后期发现Laes以来，在$ z \ sim 0 $至$ z \ sim 10 $的光度（光谱）上（频谱上）识别了十（1）多名LAE。这些大型LAE样本可用于解决两个主要的天体物理问题，银河系的形成和宇宙电离。统计研究揭示了LAE的物理特性的一般情况：年轻的恒星种群，显着的发光功能演变，紧凑的形态，高度电离的恒星间介质（ISM），具有低金属/灰尘内容物，低质量的深色黑色晕晕。典型的Laes代表低质量高-U Z $星系，高$ Z $类似物的矮星系，其中一些被认为是人口III星系的候选者。这些观察性研究还指出了稀有的明亮ly $α$源超过$ \ sim 10-100 $ kpc，被称为ly $α$ blobs，其物理起源正在争论。 LAE被用作宇宙电离历史的探针，这是通过与半乳酸间培养基（IGM）的中性氢（IGM）给出的Ly $α$ damping机翼的吸收，该介质（IGM）补充了宇宙微波背景辐射和21cm观测值。 LAE的低质量和高度离子的人口可能是宇宙电离的主要来源。尽管参数中仍然存在很大的观察不确定性，但仍限制了用于宇宙电离的电离光子的预算。除了银河系的形成和宇宙电离之外，还提出了LAE对科学边界的几种新用法，例如{\ sch hi}气体在圆形培养基中的分布和大规模结构的细丝。正在进行的计划和未来的望远镜项目（例如JWST，ELT和SKA）将推动科学领域的视野。
In this series of lectures, I review our observational understanding of high-$z$ Ly$α$ emitters (LAEs) and relevant scientific topics. Since the discovery of LAEs in the late 1990s, more than ten (one) thousand(s) of LAEs have been identified photometrically (spectroscopically) at $z\sim 0$ to $z\sim 10$. These large samples of LAEs are useful to address two major astrophysical issues, galaxy formation and cosmic reionization. Statistical studies have revealed the general picture of LAEs' physical properties: young stellar populations, remarkable luminosity function evolutions, compact morphologies, highly ionized inter-stellar media (ISM) with low metal/dust contents, low masses of dark-matter halos. Typical LAEs represent low-mass high-$z$ galaxies, high-$z$ analogs of dwarf galaxies, some of which are thought to be candidates of population III galaxies. These observational studies have also pinpointed rare bright Ly$α$ sources extended over $\sim 10-100$ kpc, dubbed Ly$α$ blobs, whose physical origins are under debate. LAEs are used as probes of cosmic reionization history through the Ly$α$ damping wing absorption given by the neutral hydrogen of the inter-galactic medium (IGM), which complement the cosmic microwave background radiation and 21cm observations. The low-mass and highly-ionized population of LAEs can be major sources of cosmic reionization. The budget of ionizing photons for cosmic reionization has been constrained, although there remain large observational uncertainties in the parameters. Beyond galaxy formation and cosmic reionization, several new usages of LAEs for science frontiers have been suggested such as the distribution of {\sc Hi} gas in the circum-galactic medium and filaments of large-scale structures. On-going programs and future telescope projects, such as JWST, ELTs, and SKA, will push the horizons of the science frontiers.
