RUI: A Determination of the Fundmental Properties of Galaxies in the Local Part of the Universe

RUI：宇宙局部星系基本属性的确定

• 批准号: 9529169
• 负责人: Albert Grauer
• 金额: --
• 依托单位: University of Arkansas Little Rock
• 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 2000-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9529169&HistoricalAwards=false
• 关键词: RUI; Determination; Fundmental; Properties; Galaxies

AST-9529169 Grauer The purpose of this observationally-based research program is to measure the basic structural and color parameters of a representative sample of galaxies in the local part of the Universe. The research plan is designed to address a broad range of questions: How are structural scale lengths and measures such as the bulge-to-disk ratio related to a galaxy's Hubble type? Are these parameters significantly different for galaxies with active nuclei when they are compared to "normal" galaxies? What is a "normal" galaxy? How is the central surface brightness of a galaxy related to its Hubble type? What is the distribution of integrated magnitudes for galaxies of all types? What is the range of vertical scale heights for disk galaxies? What are the range of arm amplitudes in spiral galaxies? What can color gradients reveal concerning the age and chemical composition of stellar populations in and the dust content of galaxies? What fraction of spiral galaxies have nuclei which are not in the center of their disks? How are disk scale lengths related to the galactic environment, bulge size, and other parameters? To what extent does the spiral arm amplitude depend on the galactic environment and/or other structural parameters? The Steward Observatory 61-inch telescope, on Mt. Bigelow near Tucson, Arizona, will be used with a NICMOS3 256X256 pixel infrared photometric camera to obtain J(wavelength 1.25 micrometers) and K(wavelength 2.2 micrometers) band infrared images for a representative sample of 321 galaxies from the Uppsala General Catalogue (UGC). Collaborators will provide the corresponding optical images. This data base of structural and color information obtained over a wide range of wavelengths will be invaluable in modeling stellar populations, bulge-to-disk ratios, and surface brightness-distributions for galaxies of all types. The data should be crucial in understanding the effects of evolution in distant galaxies and will aid in understanding the morphologies of these galaxies. This information should also provide insights into active galaxies by providing the comparison objects required to determine if their global properties are as different from "normal" galaxies as are the nuclei of the galaxies. A sample data set consisting of 64 deep images of 44 galaxies has been obtained, reduced, and evaluated. The mean limiting isophotes at the 3 sigma confidence level are 20.4 magnitude per square arcsec at K band and 21.7 magnitude per square arcsec at J band in the infrared region of the spectrum. These data have been analyzed to produce radial profiles, bulge-to-disk ratios, central surface brightness, a vertical disk scale height, arm amplitudes for some nearly face-on spiral galaxies, and color gradients for 15 galaxies. When the project is completed, half of the deep images required for the entire survey of 321 galaxies will have been obtained and calibrated. In addition, the investigation of the astrophysical content of this data set will be well underway. This project will help to significantly improve research capabilities at an undergraduate institution. Students will be directly involved with science projects that are in progress. The involvement of the students in the research will substantially improve the educational experience for students at a primarily undergraduate institution by serving as the impetus for importing new ideas and forefront technology to the undergraduate students.

这个以观测为基础的研究项目的目的是测量宇宙局部有代表性的星系样本的基本结构和颜色参数。该研究计划旨在解决一系列广泛的问题：结构尺度长度和测量（如膨胀与盘的比率）如何与星系的哈勃类型相关？与“正常”星系相比，具有活动核的星系的这些参数是否显著不同？什么是“正常”星系？一个星系的中心表面亮度与它的哈勃类型有什么关系？所有类型星系的积分星等分布是怎样的？盘状星系的垂直高度范围是多少？螺旋星系臂幅的范围是什么？关于星系中恒星群的年龄和化学成分以及尘埃含量，颜色梯度能揭示什么？有多少螺旋星系的核不在其圆盘的中心？圆盘尺度的长度与星系环境、凸起大小和其他参数有什么关系？旋臂的振幅在多大程度上取决于星系环境和/或其他结构参数？位于亚利桑那州图森附近的毕格罗山的斯图尔特天文台61英寸望远镜将与NICMOS3 256X256像素红外光度照相机一起使用，为乌普萨拉总目录（UGC）中的321个星系的代表性样本获得J（波长1.25微米）和K（波长2.2微米）波段的红外图像。合作者将提供相应的光学图像。这个在大波长范围内获得的结构和颜色信息的数据库对于模拟所有类型星系的恒星群、凸盘比和表面亮度分布将是非常宝贵的。这些数据对于理解遥远星系演化的影响至关重要，并将有助于理解这些星系的形态。这些信息还应该通过提供所需的比较对象来确定它们的整体属性是否与“正常”星系的核心一样不同，从而提供对活动星系的深入了解。一个由44个星系的64个深度图像组成的样本数据集已经获得，减少和评估。在3 σ置信水平上，光谱红外区K波段的平均限制同色团为20.4等/平方弧秒，J波段为21.7等/平方弧秒。对这些数据进行分析，得出了径向轮廓、凸起与圆盘的比率、中心表面亮度、垂直圆盘尺度高度、一些接近正面的螺旋星系的臂幅，以及15个星系的颜色梯度。当这个项目完成时，对321个星系进行全面调查所需的一半深度图像将被获得并校准。此外，对该数据集的天体物理内容的研究也将顺利进行。该项目将有助于显著提高本科院校的研究能力。学生将直接参与正在进行的科学项目。学生参与研究将大大改善本科院校学生的教育体验，为本科生引进新思想和前沿技术提供动力。