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光辐射分子云的压缩和剥离
Javier R Goicoechea1, Jérôme Pety2,3, Sara Cuadrado1
1Grupo de Astrofísica Molecular, Instituto de Ciencia de Materiales de Madrid (CSIC), Calle Sor Juana Ines de la Cruz 3, E-28049 Cantoblanco, Madrid, Spain.
Nature
|August 12, 2016
概括
高分辨率的观测显示出一个动态,碎片化的分子云表面. 与静态模型相反,气体类型之间的过渡是紧密的,表明高压波的压缩.
科学领域:
- 天文学与天体物理学
- 星际介质物理
- 恒星反机制
背景情况:
- 猎户座的星条是研究分子云面的关键地点,
- 之前的研究表明,电离和离散前线之间存在显著的空间分离,静态平衡模型预测了不均的云结构.
- 了解这些结构对于理解恒星反如何影响恒星形成区域至关重要.
研究的目的:
- 在前所未有的分辨率下调查猎户座棒分子云表面的结构和动态.
- 测试静态平衡模型的预测与新的观测数据.
- 确定不同气体相变 (H/H2和C+/C/CO) 的空间关系.
主要方法:
- 使用高分辨率 (一弧秒) 毫米波成像来解析分子云表面.
- 分析H2的振动辐射以确定H/H2的转换.
- 观察到的CO和HCO+排放,以绘制分子气体和离子碳区域的边缘.
主要成果:
- 与静态模型相反,在H/H2过渡和CO/HCO+排放边缘之间没有发现显著的偏移.
- 分子云表面呈现出高密度基层结构的碎片式山脊.
- 在云层表面观察到光衰减气体流动和不稳定的证据.
结论:
- 在空间上,H/H2和C+/C/CO过渡区是相同的,这挑战了之前的假设.
- 观察到的碎片和动态表明云端正在被高压波压缩.
- 动态和非平衡过程在分子云表面的演化中起着重要作用.
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