银河系的块状分布可以通过X射线观测来检测吗?
1Astronomy Department, University of California, Berkeley, California 94720, USA.
Nature
|July 7, 1972
概括
已公布的X射线望远镜数据无法揭示源集群的背景辐射表面亮度波动. 目前的观测缺乏检测这些微妙的宇宙结构及其对宇宙X射线背景的影响的灵敏度.
科学领域:
- 宇宙微波背景辐射宇宙微波背景辐射
- 银河系外天文学 银河系外天文学
- X射线天文学X射线天文学
背景情况:
- 宇宙X射线背景 (CXB) 是来自众多未解决来源的X射线辐射的扩散发光.
- 了解CXB表面亮度的空间波动可以提供对这些源的分布和聚类的见解.
- 之前的研究依靠X射线望远镜数据来探测CXB,但存在局限性.
研究的目的:
- 评估现有公布的X射线望远镜数据对于探测宇宙X射线背景表面亮度波动的充分性.
- 确定当前数据是否可以显示出对CXB有贡献的源集群或超级集群的证据.
主要方法:
- 对公开可用的X射线望远镜观测数据的分析.
- 在CXB内对表面亮度变化的统计调查.
- 观察到的波动与源集群理论预测的比较.
主要成果:
- 公布的X射线望远镜数据不足以解决源集群引起的表面亮度波动.
- 当前仪器的灵敏度不允许检测微妙的变化归因于X射线发射器的大规模结构.
- 现有的数据集无法证实或否认影响CXB的重大源超级集群的存在.
结论:
- 目前的X射线观测数据不足以通过CXB表面亮度波动来研究X射线源的聚类特性.
- 未来的X射线任务需要提高灵敏度,以探测这些小规模结构及其对宇宙X射线背景的贡献.
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