Galaxy Evolution and Environment

星系的形成和演化与它们所处的环境和大尺度结构密切相关。 星系群和星系团提供了一个独特的实验室来研究一系列环境的影响，直到宇宙中的星系，对星系演化和星星形成的历史。对星系团演化的研究，包括星系群、星系团形态、星系团合并、星系团质量函数和巨型中央星系（称为布里渊星系团星系，或BGC）的形成，揭示了许多与星系形成和演化、大尺度结构的生长和宇宙学直接相关的问题。* 我的建议将基于三个大型的星系团调查，旨在优化红移（z）大于1的星系团的研究（或者，当宇宙小于其当前年龄的一半时）。已经完成数据采集和处理的两项调查是：（斯皮策适应红序列星团巡天）巡天，该巡天利用斯皮策空间望远镜的红外成像与地面望远镜的光学成像相结合，产生z>1的200多个星团的目录; GCLASS（Gemini Cluster Astrophysical Science Survey）获得了9个富星系团中400多个星系团的z~1光谱。第三个是正在进行的GoGreen项目（Gemini Observations of Galeries in Early Rich Environments），这是双子座天文台批准的大型项目，将获得z>1的21个星系团和星系群中约1000个星系团成员的光谱。我的建议的一个关键科学目标是使用这些大型的光谱和光度表来探索星系中星星形成的抑制时间尺度。这将通过检查星系团不同位置的星系的各种恒星形成指标来完成。另一个主要项目是调查星系团和不同星系密度区域中合并星系的频率和类型，使我们能够深入了解合并对诱导和淬灭星星形成的贡献。我还将使用非常广泛的集群和星系目录调查星系团的形状作为时代的函数和探测星系团的形态集群演化和集群星系人口之间的联系，比较这些结果与模拟。我们的目标是调查如何集群形态与集群的质量积累和恒星的集群内容。

The formation and evolution of galaxies is intimately tied to the environment and large scale structure in which they reside. Galaxy groups and clusters provide a unique laboratory to study the effects of a range of environments, up to that of the densest in the universe, on galaxy evolution and the history of star formation. The study of cluster evolution, including the galaxy population, cluster morphology, mergers, cluster mass function and the build-up of the giant central galaxy (called Brightest Cluster Galaxy, or BGC) informs many issues directly related to both galaxy formation and evolution, the growth of large-scale structure, and cosmology. ***My proposal will be based on three large surveys of clusters designed to optimize the study of clusters at redshift (z) greater than 1 (or, when the universe was less than half of its current age). The two surveys already completed their data acquisition and reduction are: the SpARCS (Spitzer Adaptation of the Red-Sequence Cluster Survey) survey, which uses infrared imaging from the Spitzer Space Telescope combined with optical imaging from ground-based telescopes to produce a catalog of over 200 clusters at z>1; and GCLASS (Gemini Cluster Astrophysical Science Survey), which obtained spectra for over 400 cluster galaxies in 9 of the riches clusters from SpARCS at z~1. The third is the on-going GoGreen Project (Gemini Observations of Galaxies in Early Rich Environments), an approved large program at the Gemini Observatory, which will obtain spectra for ~1000 cluster members in 21 galaxy clusters and groups at z>1.***One key scientific goal of my proposal is to use these large spectroscopic and photometric catalogs to explore the time scale of the suppression of star formation in galaxies in-falling into groups and clusters. This will be done by examining various star-formation indicators for galaxies in different locations of the clusters. Another main project is to investigate the frequency and types of merging galaxies in clusters and different galaxy density regions, allowing us to gain insights into the contribution of mergers to both inducing and the quenching of star formation.***I will also use the very extensive cluster and galaxy catalogs to investigate the shape of galaxy clusters as a function of epoch and probe the connections between the morphology of galaxy clusters to cluster evolution and the cluster galaxy population, comparing these results with simulations. The goal is to investigate how cluster morphology correlates with the mass build-up of clusters and stellar contents of clusters.