The Structure of the Gaseous Cosmic Web

气态宇宙网的结构

• 批准号: 0506845
• 负责人: Michael Rauch
• 金额: $ 45.51万
• 依托单位: Carnegie Institution of Washington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-07-15 至 2009-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0506845&HistoricalAwards=false
• 关键词: Structure; Gaseous; Cosmic; Web

AST-0506845RauchCosmological simulations and observations of the intergalactic medium (IGM) are now indicating that most of the baryonic matter throughout the history of the Universe has remained in the form of intergalactic gas and never made it into galaxies and stars. Since the gas is very tenuous and spatially extended, changes in the metallicity, temperature, kinematics and ionization state of the IGM can persist for long periods. Observations of the absorption caused by the IGM in the spectra of background quasars reveal the often-subtle signatures of the various astrophysical processes that cause such disturbances. This project will study the general structure of the gaseous cosmic web at high redshift, with particular emphasis on the interactions between galaxies and the IGM. High-quality, high-resolution observations of absorption systems will be used to search for the kinematic signature of interstellar and intergalactic winds, while data from closely spaced quasar lines of sight will be used to measure the small scale density field and to determine the turbulent energy and bulk motions. A large part of the effort will be aimed at taking an image of the general distribution of neutral hydrogen at high redshift by seeing the glow from the IGM.The project includes multi-level educational and practical experiences for students, with particular emphasis on undergraduates from colleges in the Los Angeles area. Students will get first-hand experience of a working professional observatory, including observing trips with staff members to South America, and will be expected to complete a self-contained project.

AST-0506845Rauch对星系间介质（IGM）的宇宙学模拟和观测现在表明，整个宇宙历史中的大多数重子物质一直保持星系间气体的形式，从未形成星系和恒星。 由于气体非常稀薄且空间延伸，因此 IGM 的金属丰度、温度、运动学和电离状态的变化可能会持续很长时间。 对背景类星体光谱中 IGM 引起的吸收的观测揭示了引起此类扰动的各种天体物理过程的微妙特征。 该项目将研究高红移下气体宇宙网的一般结构，特别强调星系与 IGM 之间的相互作用。 吸收系统的高质量、高分辨率观测将用于搜索星际和星系间风的运动学特征，而来自紧密间隔类星体视线的数据将用于测量小尺度密度场并确定湍流能量和整体运动。 这项工作的很大一部分目标是通过观察 IGM 发出的光来拍摄高红移下中性氢的一般分布图像。该项目包括为学生提供多层次的教育和实践经验，特别是针对洛杉矶地区大学的本科生。 学生将获得专业天文台工作的第一手经验，包括与工作人员一起观察南美洲的旅行，并有望完成一个独立的项目。