Characterizing the Molecular Gas Contents of High Redshift Galaxies

表征高红移星系的分子气体含量

• 批准号: 1211358
• 负责人: Gregory Rudnick
• 金额: $ 31.83万
• 依托单位: University of Kansas Center for Research Inc
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-01 至 2016-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1211358&HistoricalAwards=false
• 关键词: Characterizing; Molecular; Gas; Contents; Redshift

Astrophysicists are just beginning to unravel the details of the early Universe and the history of star formation. Because molecular gas is the fuel for star formation, it is crucial to understand its characteristics when most stars formed, a time when the Universe was about 15% of its current age. The aim of this project is to test the theoretical picture of galaxy formation that makes the robust prediction that very distant star forming galaxies have large gas reservoirs. The principal investigator (PI) will perform a thorough characterization of molecular gas in very distant (high redshift) galaxies. This project involves a multi-year observing program conducted at newly commissioned radio and millimeter interferometers.These observations will be used to measure the ground state emission from carbon monoxide (CO) in seven star forming galaxies in one of the most distant known galaxy clusters. With these data the PI will derive the gas mass, gas consumption timescales, star formation efficiencies, dynamical masses, and gas fractions, and will increase the total available sample with such robust measurements by a factor of three. The PI will perform a similar analysis of about 30 galaxies by targeting a set of newly discovered high redshift over-densities. This sample size will enable a unique study of the gas contents and the physical conditions of the gas as a function of redshift and stellar mass. This analysis will be the first examination of how the molecular gas contents of high redshift galaxies depend on their environment.Educationally, the PI will design and implement an outreach program at Lawrence High School. The goals of this program are to teach research techniques, the nature of science, and the electromagnetic spectrum. Students in this program will use data from the Spitzer Space Telescope to measure the star formation rates of cluster galaxies. The program will involve 20 students and span over two years. The best two students will present their findings at an American Astronomical Society meeting. The program will be jointly run by a physics teacher at the school, a graduate student, and the PI. By providing opportunities for continuing education to the high school teacher and by providing the teacher with research tools and data, this program will become self-sustaining. The effectiveness of the activities will be rigorously and quantitatively assessed. The PI will additionally perform research with undergraduates, who will present their findings at an American Astronomical Society meeting. The PI will also organize an annual meeting of extragalactic astronomers and their students at institutes close to the PI's institution in order to provide opportunities for the students to exchange ideas and present their research.

天体物理学家刚刚开始揭开早期宇宙的细节和恒星形成的历史。因为分子气体是恒星形成的燃料，所以了解大多数恒星形成时的特征是至关重要的，那时宇宙的年龄大约是现在的15%。这个项目的目的是测试星系形成的理论图景，这使得非常遥远的恒星形成星系有大型气藏的可靠预测。首席研究员（PI）将对非常遥远（高红移）星系中的分子气体进行彻底的表征。这个项目包括一个多年的观测项目，在新投入使用的无线电和毫米干涉仪上进行。这些观测结果将用于测量在已知最遥远的星系团之一的七个恒星形成星系中一氧化碳（CO）的基态发射。根据这些数据，PI将推导出气体质量、气体消耗时间尺度、恒星形成效率、动态质量和气体分数，并将通过这种可靠的测量将可用样本总数增加三倍。PI将对大约30个星系进行类似的分析，目标是一组新发现的高红移超密度星系。这个样本量将使我们能够对气体含量和气体的物理条件作为红移和恒星质量的函数进行独特的研究。这一分析将是对高红移星系的分子气体含量如何依赖于它们的环境的首次研究。在教育方面，PI将在劳伦斯高中设计并实施一项外展计划。该计划的目标是教授研究技术，科学的本质和电磁频谱。这个项目的学生将使用来自斯皮策太空望远镜的数据来测量星团星系的恒星形成率。该项目将涉及20名学生，为期两年。最优秀的两名学生将在美国天文学会的一次会议上展示他们的发现。该项目将由该校的一名物理教师、一名研究生和PI共同运营。通过为高中教师提供继续教育的机会，并为教师提供研究工具和数据，该计划将实现自我维持。将严格和定量地评估这些活动的效力。PI还将与本科生一起进行研究，这些本科生将在美国天文学会的一次会议上展示他们的发现。PI还将在PI所在机构附近的研究所组织一次星系外天文学家及其学生的年度会议，以便为学生提供交流思想和展示研究成果的机会。