X-ray spectroscopic study for the evolution of hot plasmas in galaxies and clusters of galaxies

星系和星系团中热等离子体演化的 X 射线光谱研究

基本信息

批准号：
08404010
负责人：
OHASHI Takaya
金额：
$ 21.82万
依托单位：
TOKYO METOROPOLITAN UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1999
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08404010/
关键词：
X-ray astronomy galaxies clusters of galaxies hot plasmas a detector of X-ray

项目摘要

The purpose of this research was to understand the formation and evolution process of hot gas in elliptical galaxies and in clusters of galaxies based on X-ray spectroscopic observations mainly from ASCA, and also to develop X-ray detectors with an energy resolution better than 10 eV for new X-ray mission including ASTRO-E. Theoretical study of the plasma processes was also carried out because of its close connection in understanding the X-ray spectral data. Main achievements in the individual research area are summarized as follows.1. ASCA observations: Spatial distributions of temperature and metal abundance were obtained for near-by bright clusters. Large scale abundance gradient indicated metal production in galaxies, and presence of hot regions in the clusters outskirts showed recent occurrence of mergers with subclusters. Metallicity in elliptical galaxies were determined to be about 1 solar, and greatly extended X-ray emission was discovered around bright galaxies.2. Theoretical study: Fe-L emission process has been examined and there exists and uncertainty of 30% in the abundance determination. Emission process from recombining plasmas were studied in detail and spectral difference from collisionally ionizing plasmas were compared.3. Hardware development: Calibrations of microcalorimeters on-board ASTRO-E were carried out and various detector properties were examined and included in the response function. Development of transition edge sensors for a future X-ray mission was carried out. Thermal properties of Mo-Au bilayers were studied, and a readout system of SQUID signals cooled in a dilution refrigerator has been developed.

本研究的目的是基于主要来自ASCA的X射线光谱观测，了解椭圆星系和星系团中热气体的形成和演化过程，并开发能量分辨率优于10的X射线探测器eV 用于新的 X 射线任务，包括 ASTRO-E。由于等离子体过程与理解 X 射线光谱数据密切相关，因此还进行了等离子体过程的理论研究。各自研究领域的主要成果概括如下： 1． ASCA 观测：获得了附近明亮星团的温度和金属丰度的空间分布。大尺度丰度梯度表明星系中存在金属生产，星团外围热点区域的存在表明最近发生了与子星团的合并。椭圆星系中的金属丰度被测定为1个太阳左右，并且在明亮星系周围发现了大大扩展的X射线发射。2．理论研究：对Fe-L排放过程进行了考察，丰度测定存在30%的不确定性。详细研究了复合等离子体的发射过程，比较了碰撞电离等离子体的光谱差异。 3．硬件开发：对 ASTRO-E 上的微量热计进行了校准，并检查了各种探测器特性并将其包含在响应函数中。为未来的 X 射线任务开发了过渡边缘传感器。研究了 Mo-Au 双层的热性能，并开发了在稀释冰箱中冷却的 SQUID 信号读出系统。