COLLABORATIVE RESEARCH: Fingerprinting Stellar Halos - Tracing the Assembly of the Andromeda Galaxy with Detailed Chemical Abundances

合作研究：恒星晕指纹识别 - 用详细的化学丰度追踪仙女座星系的聚集

• 批准号: 1614081
• 负责人: Evan Kirby
• 金额: $ 37.55万
• 依托单位: California Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-07-01 至 2019-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1614081&HistoricalAwards=false
• 关键词: COLLABORATIVE; RESEARCH; Fingerprinting; Stellar; Halos

The stars in the outermost regions of galaxies preserve a fossil record of the birth of stars and dynamics of that galaxy over its lifetime. These stellar halos extend far beyond the crowded inner regions of galaxies, where the majority of the stars reside in disks or dense spheres. Stellar halos are thought to be made of stars that formed very early on, in the galaxy's newly formed disk, as well as stars that were originally part of smaller, dwarf, galaxies that fell into the large galaxy and were torn apart. The investigators will study the physical properties of the stars in the Andromeda galaxy's stellar halo, and will determine the relative importance of these two different ways of contributing stars to a galaxy's halo. Their goal is understanding of how massive galaxies grow. They will deduce the properties of destroyed "dwarf" galaxies and their rate of forming new stars. This will give insight into the properties of dwarf galaxies that did not survive until the present day. This program will train young astronomers and introduce high school students to astronomical research.The Andromeda galaxy is the nearest large galaxy to our own. It is similar in many ways to our Milky Way galaxy, but shows evidence that it has merged with more small galaxies than the Milky Way. The investigators, along with students, will use an archive of Keck telescope spectra from previous observations of tens of thousands of stars, and will also perform new spectroscopic observations. They will use the spectra to measure the abundances of atomic elements and track the properties of the chemical environment in which the stars formed. The investigators will perform the first large-scale chemical abundance study of Andromeda's stellar halo.The investigators will recruit students to engage in summer research related to this program. They will focus their recruitment at schools that have a large fraction of students from demographic groups that are under-represented in science, technology, engineering, and mathematics (STEM). Completing a cutting-edge astronomical research project will both introduce these students to working in a STEM field and give them confidence that they can succeed in a STEM career.

星系最外层区域的恒星保存着恒星诞生和该星系一生动态的化石记录。这些恒星晕远远超出了星系拥挤的内部区域，其中大多数恒星居住在圆盘或致密球体中。 恒星晕被认为是由很早形成的恒星组成的，在星系新形成的盘中，以及最初属于较小的矮星系的恒星，这些星系落入大星系并被撕裂。 研究人员将研究仙女座星系恒星晕中恒星的物理特性，并将确定这两种不同方式将恒星贡献给星系晕的相对重要性。 他们的目标是了解大质量星系是如何生长的。 他们将推断被摧毁的“矮”星系的特性及其形成新恒星的速度。 这将使我们深入了解直到今天才幸存的矮星系的特性。该计划将培训年轻的天文学家并向高中生介绍天文学研究。仙女座星系是距离我们最近的大型星系。它在很多方面与我们的银河系相似，但有证据表明它与比银河系更多的小星系合并。 研究人员和学生将使用凯克望远镜先前对数万颗恒星进行观测的光谱档案，并将进行新的光谱观测。 他们将利用光谱来测量原子元素的丰度，并追踪恒星形成的化学环境的特性。 研究人员将对仙女座星系的恒星晕进行首次大规模化学丰度研究。研究人员将招募学生从事与该项目相关的夏季研究。 他们将把招生重点放在那些学生大部分来自科学、技术、工程和数学 (STEM) 领域代表性不足的人口群体的学校。 完成尖端天文研究项目不仅可以让这些学生了解 STEM 领域的工作，还可以让他们相信自己能够在 STEM 职业生涯中取得成功。