An Investigation of Physical Factors that Determine Galaxy Structure Based upon a New Method of Quantitative Analysis.

该项目的目的是在对大量星系图像进行定量分析的基础上，了解造成各种星系结构的物理因素。5年的研究成果总结如下：1。星系结构的研究。我们发现：(1)决定星系整体结构的物理因素有两个；(2)导致星系形状多种多样的主要因素是球状成分的结构而不是盘状成分的结构；(3)星系的总光度与平均相空间密度之间存在良好的相关性。最后一个关联将成为理解暗物质存在下星系形成机制的有力工具。(4)对与定量分析有关的几个问题进行了较详细的研究。它们包括内部吸收、紫外线辐射、星系特性和图像处理技术。建立了一个包含约800个星系二维光度分布的数据库。数据库将在世界范围内分发给对它感兴趣的人。天文图像数据处理系统。在具有多种图像I/O外设的专用超小型计算机上开发了一套高效的天文图像数据处理系统。介绍了一种照相版扫描机，并成功地作为该系统的组成部分进行了操作。

The aim of the project is to understand what physical factors are responsible for the wide variety of galaxy structure on the basis of quantitative analyses of a large number of galaxy images. Results of this 5-year project are summarized as follows.1. Investigation of Galaxy Structure. We have found that (1) the number of physical factors that determine the global structure of galaxies is two, (2) the leading factor which is responsible for the wide variety of galaxian shape is the structure of the spheroidal component rather than that of the disk component, and (3) there is a well-bahaved correlation between the total luminosity of galaxies and the average phase-space density. The last correlation will ne a powerful tool to understand the mechanism of galaxy formation in the presence of dark matter. (4) Several problems related to the quantitative analyses have been studied in some detail. They include internal absorption, ultraviolet rediation, and peculiarity of galaxies, and image processing technique.2. Database of Galaxies A database has been constructed which includes two-dimensional luminosity distribution of about 800 galaxies. The detabase will be distributed on the world-wide basis to those who are interested in it.3. Astronomical Image Data Processing System. An efficient astronomical image data processing system has been developed on a dedicated superminicomputer with a variety of image I/O peripherals. A photographic plate scanning machine was introduced and has been successfully operated as an integral part of the system.