The Outer Half of Disk Galaxies

盘状星系的外半部分

• 批准号: 0907771
• 负责人: Dennis Zaritsky
• 金额: $ 26.22万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2013-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0907771&HistoricalAwards=false
• 关键词: Outer; Half; Disk; Galaxies

Dr Zaritsky will use deep optical imaging and spectroscopy with the Large Binocular Telescope to study the stellar content, history, and motions in the outer parts of galaxy disks. These regions were long known to contain gas, but until recently were thought to be making no new stars. Clumps of new stars will be mapped out using deep images in blue light, to investigate the history of starbirth in the outer galaxy, and find the true edge of the stellar disk. The motions of the stellar clumps will be measured from the Doppler shift of their spectral lines. The averaged motion will show how fast the outer parts of the galaxy rotate about its center, and the mass density of the outer disk can be inferred from the way that the motion of individual clumps of stars deviates from that mean. Dr Zaritsky will use his results to test key concepts in models for galactic evolution, such as whether the thin disks can survive the repeated mergers through which large galaxies are expected to grow; what the tightness of scaling relations implies for the development of galaxy disks; and how disk sizes could be related to the angular momentum distribution of the protogalaxy.This proposal will fund the training of a graduate student. Dr Zaritsky will use his deep galaxy images to develop laboratory exercises for his undergraduate observational astronomy class, a Vatican summer school that he has proposed for 2010, and a Study Abroad course in Ghana scheduled for winter 2009. The labs will also be made available over the internet.

Zaritsky博士将使用大型双眼望远镜使用深层的光学成像和光谱学来研究星系磁盘外部的恒星含量，历史和运动。 这些地区早已众所周知，这些地区含有气体，但直到最近才被认为没有新的恒星。新恒星的团块将使用蓝光中的深色图像进行绘制，以研究外部星系中星天气的历史，并找到恒星磁盘的真实边缘。 恒星团块的运动将从光谱线的多普勒移位进行测量。 平均运动将表明银河系的外部在其中心旋转的速度，并且外盘的质量密度可以从单个恒星的运动偏离该平均值的方式来推断出。 Zaritsky博士将使用其结果来测试银河进化模型中的关键概念，例如薄磁盘是否可以在预期大星系增长的重复合并中生存；扩展关系的紧密性意味着银河系磁盘的发展；磁盘尺寸如何与原galaxy的角动量分布有关。该提案将资助研究生的培训。 Zaritsky博士将使用他的深层银河图像为他的本科生观察天文学课程开发实验室练习，这是他在2010年提出的梵蒂冈暑期学校，以及计划于2009年冬季的加纳留学课程。实验室还将通过互联网提供。