发现原恒星外流物体HH2的X射线
S H Pravdo1, E D Feigelson, G Garmire
1Jet Propulsion Laboratory, California Institute of Technology, Mail Stop 306-438, 4800 Oak Grove Drive, Pasadena, California 91109, USA. spravdo@jpl.nasa.gov
Nature
|October 19, 2001
概括
天文学家检测到来自Herbig-Haro (HH) 物体的X射线,证实了这些恒星形成区域的冲击加热气体. 这一发现支持喷射诱导冲击模型的HH物体形成.
科学领域:
- 天体物理学 天体物理学
- 天文学 天文学
- 恒星进化 恒星进化
背景情况:
- 赫比格-哈罗 (HH) 物体是恒星形成区域的发光气体凝聚物.
- 它们的物理性质一直受到争议,模型包括新生恒星,恒星风和冲击激发的气囊.
- 喷气诱导冲击模型预测了来自高能量HH物体的X射线辐射.
研究的目的:
- 为了调查来自赫比格-哈罗天体的X射线辐射的存在.
- 为了测试喷气诱导冲击模型的预测.
主要方法:
- 对赫比格-哈罗物体HH2的观测,它是最明亮和最接近的物体之一.
- 对X射线辐射水平的分析和与理论模型的比较.
主要成果:
- 从赫比格-哈罗天体HH2.2中检测到X射线辐射.
- 检测到的X射线水平与喷气诱导冲击模型的预测保持一致.
- 辐射源于物体前边的冲击加热材料.
结论:
- 这一发现为喷气式冲击模型提供了有力的证据.
- 赫比格-哈罗物体含有冲击加热的材料,温度约为106K.
- 这一发现提升了我们对恒星形成的物理过程的理解.
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