对马格伦冠状的观察
Dhanesh Krishnarao1,2,3, Andrew J Fox4, Elena D'Onghia5
1Space Telescope Science Institute, Baltimore, MD, USA. dkrishnarao@coloradocollege.edu.
Nature
|September 28, 2022
概括
科学家发现大麦哲伦云 (LMC) 和小麦哲伦云 (SMC) 周围有一个温暖的气体光环, 这一发现有助于我们了解这些星系的演变及其与银河系的相互作用.
科学领域:
- 银河系外的天文学
- 银河系的演变
- 宇宙气体物理
背景情况:
- 大麦哲伦云 (LMC) 和小麦哲伦云 (SMC) 是银河系附近的卫星星系.
- 之前的质量测量表明LMC应该有一个热的气体光环 (马格兰王冠).
- 这种气体结构被认为受到光环的影响.
研究的目的:
- 为了找到预测的马格兰冠状病毒的证据.
- 描述围绕LMC和SMC的环银河系介质 (CGM).
- 在银河系动力学和气体积聚中发挥的作用.
主要方法:
- 利用背景类星体的紫外线 (UV) 吸收光谱.
- 搜索高度电离物种的光谱特征,例如O+5,C+3和Si+3.
- 分析了麦哲伦CGM中的气体的空间分布和离子化状态.
主要成果:
- 通过检测O+5吸收呈现了马格兰冠状病毒的证据.
- 通过C+3和Si+3吸收间接检测到冠状病毒.
- 具有至少35Kpc的多相马格兰CGM的特征,总电离质量为~10^9.1M.
结论:
- 马格伦冠状病毒的存在得到证实,
- 马格拉尼冠状病毒是大型多相CGM的组成部分.
- 这一发现对于理解马格伦系统的特性及其在本地群体内的共同进化至关重要.
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