Galaxy Evolution: Tidal Remnants, Outflows, and Inflows

星系演化：潮汐残余、流出和流入

• 批准号: 1203059
• 负责人: Kathleen Barger
• 金额: $ 8.9万
• 依托单位: Barger-Seim Kathleen A
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-01 至 2014-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1203059&HistoricalAwards=false
• 关键词: Galaxy; Evolution; Tidal; Remnants; Outflows

Dr. Kathleen Barger is awarded an NSF Astronomy and Astrophysics Postdoctoral Fellowship to carry out a program of research and education at the University of Notre Dame. One of the most pressing problems in galaxy formation concerns how gas accretion and feedback influence the evolution of galaxies. Galaxy evolution is regulated by the ability of galaxies to accrete and retain gas to continue star formation, but how does matter cycle in and out of galaxies? Recent theoretical studies suggest that predominantly ionized material may infall onto galaxies through intergalactic filaments, but it is unclear whether the gas will evaporate in the halo before reaching the galactic disk. In contrast, feedback from massive stars expels gas and quenches star formation by heating and ionizing the gas. To understand outflow and inflow processes in galaxies at greater distances, the fellow in this project will study them in the local Universe, where they can be studied in detail.To decipher the flows in the circumgalactic gas of the Milky Way, the fellow will combine Wisconsin H-Alpha Mapper (WHAM) optical and Hubble Space Telescope ultraviolet spectroscopic observations of the Large Magellanic Cloud (LMC) outflow and Magellanic Stream to test if dwarf galaxies can sustain massive galaxy star formation and to test the origin of the gaseous structures feeding galaxies. The Magellanic Clouds are nearby enough to exploit the power of absorption- and emission-line spectroscopy, allowing investigators to measure the density, temperature, metallicity, kinematics, and morphologies of the diffuse circumgalactic gas. Through these observations the fellow will investigate the LMC stellar outflows and the Magellanic Stream to determine their basic physical properties, the source of their ionization, their extent and morphology, and their fate. Establishing a new perpective of the gaseous flows in our own Galactic environment will provide a firmer basis to understand the implications of gas detected far from galaxies throughout the Universe.The broader impacts of this project include a significant educational component. The fellow will create a Professional Resource Development program for the Physics Department at the University of Notre Dame. This program will consist of an annual professional development seminar along with complementary workshops. The Professional Resource Development seminar will include topics on traditional academic and alternative career paths, networking, and job applications in conjunction with members of the Professional Development Committee at Notre Dame, whose membership includes the Kaneb Center for Teaching and Learning, Writing Center, Graduate School, English for Academic Purposes, Reilly Center for Science, among others. Each summer this program will include three workshops on Curriculum Vitae, research statements, and cover letters and will stress the importance of strong communication skills and tailoring documents to different audiences. The fellow's program in the Physics Department will serve as a model for similar professional development resources applicable across the College of Science.

Kathleen Barger博士被授予NSF天文学和天体物理学博士后奖学金，在圣母大学开展研究和教育计划。 星系形成中最紧迫的问题之一是气体吸积和反馈如何影响星系的演化。 星系的演化是由星系吸积和保留气体以继续星星形成的能力来调节的，但是物质是如何在星系中循环进出的呢？ 最近的理论研究表明，主要电离的物质可能会通过星系际细丝落入星系，但尚不清楚气体在到达银盘之前是否会在晕中蒸发。 相比之下，来自大质量恒星的反馈通过加热和电离气体排出气体并淬灭星星的形成。 为了了解更远距离星系中的流出和流入过程，该项目的研究员将在本地宇宙中研究它们，在那里可以详细研究它们。为了破译银河系环银河系气体的流动，该研究员将把联合收割机威斯康星州的H-阿尔法成像仪（WHAM）光学和哈勃太空望远镜对大麦哲伦云（LMC）的紫外光谱观测结合起来外流和麦哲伦流，以测试矮星系是否可以维持大质量星系星星的形成，并测试供应星系的气体结构的起源。 麦哲伦云足够近，可以利用吸收线和发射线光谱的力量，使研究人员能够测量扩散的环银河系气体的密度，温度，金属丰度，运动学和形态。 通过这些观测，研究员将研究LMC恒星流出和麦哲伦流，以确定它们的基本物理特性，电离源，它们的程度和形态以及它们的命运。 在我们自己的银河系环境中建立一个新的气体流动的视角将为理解在整个宇宙中远离星系检测到的气体的含义提供一个更坚实的基础。 该研究员将为圣母大学物理系创建一个专业资源开发计划。 该计划将包括一个年度专业发展研讨会沿着补充讲习班。 专业资源开发研讨会将包括传统学术和替代职业道路，网络和工作申请的主题，与圣母大学专业发展委员会的成员一起，其成员包括Kaneb中心的教学和学习，写作中心，研究生院，学术英语，赖利科学中心等。 每年夏天，该计划将包括三个关于简历，研究声明和求职信的研讨会，并将强调强大的沟通技巧和为不同受众定制文件的重要性。 该研究员在物理系的计划将作为整个科学学院适用的类似专业发展资源的典范。