Bright Field Galaxies and their Dark Matter Halos

明场星系及其暗物质晕

• 批准号: 0708468
• 负责人: Tereasa Brainerd
• 金额: --
• 依托单位: Trustees of Boston University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-08-15 至 2011-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0708468&HistoricalAwards=false
• 关键词: Bright; Field; Galaxies; their; Dark

AST-0708468BrainerdAlthough it is generally accepted that massive dark matter halos surround all large, bright galaxies, many of the basic properties of galaxy-sized dark matter halos remain poorly constrained. This project focuses on using small, faint satellite galaxies, orbiting within the gravitational potentials of large, bright field galaxies, to obtain a substantial improvement over the current halo constraints. The research will use a combination of theory, archival and new observations, and numerical datasets, to address a) the best halo virial mass estimator, b) how best to measure the velocity dispersion of satellite galaxies, c) the dependence of the mass-to-light ratio on luminosity, and whether this differs for early- and late-type galaxies, d) whether the halos of late-type galaxies are fundamentally different from those of early-type galaxies, and e) whether the angular momentum of a disk galaxy closely correlates with the net angular momentum of its halo.The principal investigator will participate in Lowell Observatory's successful outreach program, targeting fifth through eighth grade students at Navajo and Hopi Nation Schools. This teacher-astronomer partnership is a significant commitment of time, including classroom visits, timed to coincide with observing runs, and an extended field trip for the students. The research will contribute to the professional development of a graduate student. All of the genuine and simulated data, and the software used, will be publicly available.

尽管人们普遍认为大质量暗物质晕环绕着所有大而明亮的星系，但星系大小的暗物质晕的许多基本性质仍然没有得到很好的约束。这个项目的重点是使用小的，微弱的卫星星系，在大的，明亮的领域星系的引力势内运行，以获得对目前晕轮限制的实质性改进。这项研究将使用理论、档案和新观测以及数值数据集相结合的方法，讨论a)最好的晕维里质量估计器，b)如何最好地测量卫星星系的速度离散度，c)质量光比与光度的关系，以及这对早类型和晚类型星系的影响是否不同，d)晚类型星系的晕是否与早类型星系的晕有根本不同，e)盘星系的角动量是否与其晕的净角动量密切相关。主要研究人员将参与洛厄尔天文台成功的扩展计划，目标是纳瓦霍和霍皮民族学校的五年级到八年级学生。这种教师和天文学家的合作关系是对时间的重大承诺，包括课堂访问，时间安排在观察跑步的同时，以及学生的长期实地考察。这项研究将有助于研究生的专业发展。所有真实的和模拟的数据以及使用的软件都将公开可用。