由扩展的磁盘风驱动的原恒星外流的分辨率图像
Per Bjerkeli1,2, Matthijs H D van der Wiel1,3, Daniel Harsono4
1Centre for Star and Planet Formation, Niels Bohr Institute &Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5-7, 1350 Copenhagen K, Denmark.
Nature
|December 16, 2016
概括
年轻的恒星通过圆盘风喷射气体, 消除角动量以促进生长. 解析图像显示这种流出源自原恒星盘的扩展区域,而不仅仅是恒星本身.
科学领域:
- 天体物理学
- 恒星进化
- 原恒星的外流
背景情况:
- 年轻的恒星表现出强大的分子气体流出,这对于角动量去除和恒星通过积累增长至关重要.
- 出流发射的确切机制和位置尚不清楚,模型提出恒星风或圆盘风.
研究的目的:
- 研究与年轻恒星相关的分子外流的发射区域.
- 解决原恒星系统中气体喷射和角运动量去除的空间范围.
主要方法:
- 使用一氧化碳 (CO) 排放的分辨率成像.
- 专注于与TMC1A原恒星系统相关的外流气体.
主要成果:
- 通过高分辨率的图像,可以看到从中心原恒星喷射出长达25天文单位的气体.
- 证明了角运动量从原恒星盘的延伸区域被移除.
结论:
- 这些发现支持扩展盘式风向外流发射模型.
- 出流的气体来自原恒星盘的重要部分,而不仅仅是恒星周围.
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