Galactic History- Old Stellar Populations in Edge-on Disk Galaxies

银河历史-边缘盘星系中的古老恒星群

• 批准号: 9624542
• 负责人: Heather Morrison
• 金额: $ 53.24万
• 依托单位: Case Western Reserve University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-08-01 至 2003-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9624542&HistoricalAwards=false
• 关键词: Galactic; History; Old; Stellar; Populations

9624542 Morrison The ability to study old stellar populations in galaxies, the results of which may be used to trace the formation and evolution of galaxies, has benefited in several ways from the advent of large-format Charge-Coupled-Devices (CCDs) and increased computing power. A major advance has been the development of techniques of using deep CCD imaging of galaxies, which allows one to study the old stellar populations of nearby galaxies in unprecedented detail. The observations to be carried out will reach more than 2 magnitudes fainter than previous observations. The results of the research will serve to delineate the older stellar populations of a representative sample of nearby disk galaxies, using recently developed techniques. A systematic investigation of the properties of 10 nearby edge-on disk galaxies with Hubble types ranging from Sc though Sa to S0 will be carried out. Of particular interest in this work are the properties of thick disks and stellar halos of these galaxies, when they exist. The study of the thick disks observed in the sample will able one to test the currently popular models of thick disk galaxy formation by satellite accretion. If the models predict successfully the thick disk properties of this sample, there is the possibility of using thick disks as tracers of the accretion history of galaxies. The characterization of thick disks and halos in this sample will allow us to test for the first time whether the Milky Way's old stellar populations are typical of nearby disk galaxies. Most of the observations will be taken on Case Western Reserve University's (CWRU) Burrell Schmidt telescope at Kitt Peak Natal Observatory (KPNO), to which CWRU has special access. An improved CCD system for the Schmidt, with a factor of 5 improvement in quantum efficiency, will be purchased. This upgrade of the CCD system will enable surface photometry observations in the blue region of the spectrum, and thus provide color (and hence a ge and metallicity) information on the thick disk and halo stellar populations. Teaching development activities will include involvement of undergraduate students in research and in course development of the "Introduction to Astronomy for Majors" course. This will closely tie what is taught to current research, using a thematic approach. Two major areas of current astronomical research, how the solar system was formed and the determination of the value of cosmic distance scale problem, will be used as recurring themes in the two-semester course. Other teaching-related activities will include several innovative ways of improving teaching, organized through CWRU's new teaching center (including active learning techniques and a strong use of the World Wide Web). A program to allow undergraduates to accompany the PI on observing trips to KPNO will be carried out. ***

9624542 Morrison 研究星系中古老恒星群的能力，其结果可用于追踪星系的形成和演化，在几个方面受益于大型电荷耦合器件（CCD）的出现，并增加了计算能力。 一项重大进步是使用星系深度 CCD 成像技术的发展，这使得人们能够以前所未有的细节研究附近星系的古老恒星群。即将进行的观测将比之前的观测暗2个星等以上。 研究结果将利用最近开发的技术来描绘附近盘状星系代表性样本中较古老的恒星种群。 将对附近 10 个哈勃类型从 Sc 到 Sa 到 S0 的边缘盘星系的特性进行系统研究。 这项工作特别令人感兴趣的是这些星系的厚盘和恒星晕（当它们存在时）的特性。 对样本中观察到的厚盘的研究将能够测试当前流行的通过卫星吸积形成的厚盘星系模型。如果模型成功预测了该样本的厚盘特性，就有可能使用厚盘作为星系吸积历史的示踪剂。 该样本中厚盘和光晕的特征将使我们能够首次测试银河系的古老恒星群是否是附近盘状星系的典型特征。 大部分观测将在凯斯西储大学 (CWRU) 位于基特峰纳塔尔天文台 (KPNO) 的 Burrell Schmidt 望远镜上进行，CWRU 拥有特别访问权限。 将为施密特购买改进的 CCD 系统，量子效率提高 5 倍。 CCD 系统的升级将使光谱蓝色区域的表面光度测量成为可能，从而提供有关厚盘和晕恒星群的颜色（以及因此的 ge 和金属丰度）信息。 教学开发活动将包括本科生参与“专业天文学概论”课程的研究和课程开发。 这将使用主题方法将所教授的内容与当前的研究紧密联系起来。 当前天文学研究的两个主要领域，太阳系的形成和宇宙距离尺度问题的价值确定，将作为两个学期课程中反复出现的主题。其他与教学相关的活动将包括通过 CWRU 的新教学中心组织的几种改进教学的创新方法（包括主动学习技术和万维网的大力使用）。 将实施一项允许本科生陪同 PI 前往 KPNO 进行观察旅行的计划。 ***