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Updated: Jul 7, 2025

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两个质量损失过程的历史在VY CMa中
G Quintana-Lacaci1, L Velilla1, J P Fonfría1
1Dept. of Molecular Astrophysics. IFF-CSIC; Centro de Astrobiología (CAB), CSIC-INTA; Instituut voor Sterrenkunde, KU Leuven; Institut de Radio Astronomie Millimétrique.
概括
巨大的红超巨星通过两个不同的过程喷射物质:巨大的,不规则的外流和局部的,快速的外流. 这些发现揭示了对这些恒星的质量损失机制的新见解.
科学领域:
- 天文学 天文学
- 天体物理学 天体物理学
- 恒星进化 恒星进化
背景情况:
- 红超巨星 (RSG) 众所周知具有显著的质量喷射.
- 驱动RSG质量损失的确切机制尚未完全理解.
- 以前的假设包括阿尔夫文波,对流细胞和MHD干扰.
研究的目的:
- 为了研究红超巨星中未知的质量喷射机制.
- 分析VY CMa.周围喷射的详细结构和动力学.
- 提供关于RSG质量丧失过程和恒星演变的基本信息.
主要方法:
- 使用高角度分辨率的干涉测量阿塔卡马大毫米/亚毫米阵列 (ALMA) 地图.
- 使用连续和分子排放数据重建气体的3D结构.
- 分析环恒星物质的形态和动力学.
主要成果:
- 观察到两种不同类型的喷射物:延伸的,不规则的材料和局部的,快速的外流.
- 发现外流特别平坦,并证明它们对周围材料的雕刻效应.
- 成功重建了这些流出的3D结构.
结论:
- 证实VY CMa中至少有两种不同的质量损失过程活跃.
- 暂时提出了两个观察到的喷射物类型形成的物理原因.
- 提供了了解红超巨星质量损失和演变的关键数据.
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