年轻恒星周围圆盘中的南极流
Richard Teague1, Jaehan Bae2, Edwin A Bergin3
1Department of Astronomy, University of Michigan, Ann Arbor, MI, USA. rteague@umich.edu.
Nature
|October 18, 2019
概括
一颗年轻恒星的原行星盘中的气体流动表明行星的形成正在积极发生. 这些观测到的"午线流"为行星如何在这些尘土盘中收集物质和生长提供了新的见解.
科学领域:
- * 天文学与天体物理学
- * 星球科学
背景情况:
- * 原行星盘表现出像环和空隙这样的子结构,通常归因于形成行星或水力动态不稳定.
- * 气体速度结构对于理解圆盘演变,物质运输和行星形成过程中的角动量移除至关重要.
研究的目的:
- * 调查年轻恒星HD 163296周围的原行星盘上层的气体速度结构.
- * 确定观察到的磁盘子结构是否与特定的气体流动模式相关.
主要方法:
- * 用12CO排放测量了三种气体速度组件的辐射形状.
- * 观测集中在HD 163296原行星盘的上层.
主要成果:
- 在已知的空隙的辐射位置检测到大量的气体从磁盘表面向中平面流动.
- * 这些流动与与早期行星形成相关的预测午线流动非常相似.
- 在圆盘的外缘观察到持续的辐射外流,这可能表明恒星风的基础.
结论:
- * 观察到的气体流支持嵌入行星雕塑盘间隙并将物质推向中平面的假设.
- * 这些发现为行星形成和圆盘演变的理论模型提供了观测证据.
- * 这项研究强调了气体动态在行星形成和原行星盘内角动量传输中的作用.
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