Collaborative Research: Stellar Clouds as New Probes of the Milky Way's Accretion History and Mass Distribution.

合作研究：恒星云作为银河系吸积历史和质量分布的新探测器。

• 批准号: 1312196
• 负责人: Kathryn Johnston
• 金额: $ 33.46万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1312196&HistoricalAwards=false
• 关键词: Collaborative; Research; Stellar; Clouds; New

What are the radial profiles, shapes, extents and orientations of the dark matter halos that surround galaxies? This fundamental question is particularly difficult to address in the outskirts of galaxies where there are few visible tracers. Perhaps the most promising approach is to use stellar debris from the destruction of satellite galaxies, and the most promising place to try this approach is the Milky Way - the one galaxy in the Universe where a halo's 3-dimensional structure (rather than a 2-dimensional projection) can be directly probed.This award will support a combined observational and theoretical approach to providing a new and powerful perspective on accreted halo substructures, and, in particular, poorly-studied stellar clouds. The observational program focuses on obtaining radial velocities for stars in known stellar clouds, and making connections between debris structures - from the Solar vicinity to the outer Galaxy, and from one side of the Galaxy to another. Such connections will yield the first comprehensive maps of these stellar debris structures on Galactic scales. Interpreting these maps with a systematic suite of simulations will fill in our missing knowledge of the Galaxy's accretion history and matter distribution.This award will support the training of one minority student in their transition from undergraduate to graduate school through participation in Columbia's "Bridge to the PhD" program. It will also enable the PIs to actively engage students, amateur astronomers and the general public in building an understanding of the history of our home galaxy.

围绕星系的暗物质晕的径向轮廓、形状、范围和方向是什么？这个基本问题在星系的外围特别难以解决，那里几乎没有可见的示踪剂。也许最有希望的方法是利用卫星星系毁灭后的恒星碎片，最有希望尝试这种方法的地方是银河系--宇宙中唯一一个星系，（而不是二维投影）该奖项将支持一种结合了观测和理论的方法，以提供一个新的和强大的视角，晕子结构，特别是研究不足的恒星云。观测计划的重点是获得已知恒星云中恒星的径向速度，并在碎片结构之间建立联系-从太阳附近到外星系，从银河系的一侧到另一侧。这样的连接将产生第一个全面的地图，这些恒星碎片结构在银河系的规模。用一套系统的模拟解释这些地图将填补我们对银河系吸积历史和物质分布的缺失知识。这个奖项将支持一名少数民族学生通过参加哥伦比亚的“通往博士的桥梁”项目从本科过渡到研究生院。它还将使PI能够积极吸引学生，业余天文学家和公众，以建立对我们银河系历史的理解。