在恒星HD14156969周围的原行星盘中的CO和H3+)
Sean D Brittain1, Terrence W Rettig
1University of Notre Dame, Center for Astrophysics, Notre Dame, Indiana 46556, USA.
Nature
|July 5, 2002
概括
研究人员检测到大质量恒星HD141569.9周围的一氧化碳 (CO) 和 (H3+) 排放. 这一发现为围绕大质量恒星快速形成的气体巨行星提供了线索.
科学领域:
- 天文学和天体物理学
- 外系行星科学 外系行星科学
- 恒星和气体磁盘动力学
背景情况:
- 许多恒星周围已经发现了大质量行星,但气体巨行星形成的时间表仍然是一个关键问题.
- 大质量恒星可能会迅速分散它们周围的气体,这可能会阻碍原行星核心的积聚.
- 在Herbig AeBe恒星周围探测出原行星 (太阳质量的2-3倍) 可以限制行星形成的时间表.
研究的目的:
- 为了研究大质量恒星周围的行星形成时间表.
- 为了寻找原行星盘在赫尔比格AeBe恒星HD141569.9周围演化的证据.
- 分析HD141569.9盘中的气体和潜在的原行星的分布.
主要方法:
- 来自原行星盘的一氧化碳 (CO) 排放的检测.
- 来自原行星盘的三酸 (H3+) 排放的检测.
- 解释排放数据以推断磁盘的组成和结构.
主要成果:
- 检测到的CO和H3+排放来自5-10万年前的Herbig AeBe恒星HD141569.
- CO数据表明,内部盘已经清除了超过17个天文单位,过去的早期积累阶段.
- 二氧化碳和H3+的同时存在令人惊,因为二氧化碳通常会破坏H3+.
结论:
- 观察到的CO和H3+可能在磁盘内空间分离.
- 另外,H3+排放可能源自原行星的扩展大气层.
- 这一检测为围绕大质量恒星的行星形成过程提供了关键证据.
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