Observations of the z=1-4 Universe

AST-0070773Steidel这项工作包括对高红移星系的物理性质、大尺度分布和星星形成特征的详细研究。PI将使用宽视场成像来绘制发光材料的大尺度结构，并将其与类星体吸收线研究联合收割机相结合，以绘制和识别相关的中间红移（z = 1.3至2.5）气体。这些中等红移天体的星星形成率、它们的化学成分以及它们与气体的关联将随后使用近红外光谱进行分析。这些研究的重点是星系的性质和它们在宇宙时间间隔内的大尺度空间分布，当时宇宙的年龄在10%到40%之间。这个时间间隔被认为是星系形成活动的时期，产生了今天宇宙中的星系，也是今天宇宙中大多数恒星形成的时期。 在过去的几年里，设备和技术已经变得可用，这使我们能够收集有关这些早期宇宙时代星系的广泛经验数据。 这里提议的研究将利用帕洛玛和凯克天文台的设施：1）"绘制"早期星系在空间体积上追踪到的大尺度结构，可与当地宇宙最雄心勃勃的星系调查相媲美2）将早期的星系分布与相同体积中弥漫的星系际气体的性质进行比较（使用补充技术进行观测）3）探索新技术，在目前最难观测到的时间间隔-宇宙处于"中年"时-发现和研究大样本星系;测量这些早期星系重要样本的化学含量和质量。 所有这些研究都是为了在宇宙学模型的背景下，对星系形成过程的物理理解取得重大进展，在宇宙学模型中，星系的形成和演化是宇宙中物质分布随时间变化的可观察表现。该项目的资金由美国国家科学基金会的星系外天文学宇宙学计划（AST/EXC）提供。&

AST-0070773SteidelThis work involves the detailed study of the physical properties, large-scale distribution, and star forming characteristics of high redshift galaxies. The PI will use wide-field imaging to map out the large scale structure of the luminous material and combine this with quasar absorption line studies to map out and identify the associated intermediate redshift (z=1.3 to 2.5) gas. The star formation rates for these intermediate redshift objects, their chemical composition, and their association with the gas will then be analyzed using near IR spectroscopy. These studies focus on the properties of galaxies and their large--scale spatial distribution during an interval of cosmic time when the universe was between 10% and 40% of its current age. This time interval is believed to be the epoch when when the galaxy formation activity that produced the galaxies of the present-day universe was at its peak and when most of the stars in the present day universe formed. In the last few years, facilities and techniques have become available, which allow us to gather extensive empirical data on galaxies at these early cosmic epochs. The studies proposed here will use the facilities of the Palomar and Keck observatories to: 1) ``map'' the large-scale structure traced by early galaxies over volumes of space comparable to the most ambitious galaxy surveys of the local universe 2) compare the galaxy distribution at early epochs to the properties of the diffuse intergalactic gas in the same volumes (observed using complementary techniques) 3) explore new techniques for finding and studying large samples of galaxies in the time interval that is currently least accessible to observation-- when the universe was ``middle aged'' and 4) measure the chemical content and masses of significant samples of these early galaxies. All of these studies are intended to make significant progress toward a physical understanding of the galaxy formation process, in the context of cosmological models in which galaxy formation and evolution is the observable manifestation of the changing distribution of matter in the universe as a function of time. Funding for this project was provided by the NSF program for ExtragalacticAstronomy & Cosmology (AST/EXC).***