在年轻恒星周围的碎片盘中存在大量分子的储存库
W F Thi1, G A Blake, E F van Dishoeck
1Leiden Observatory, PO Box 9513, 2300 Leiden, The Netherlands.
Nature
|May 9, 2001
概括
对分子 (H2) 的观测揭示了恒星碎片盘中的大量气体,挑战了基于一氧化碳的先前发现. 这一发现表明碎片盘可能比以前认为的保留了更多的气体,影响行星形成理论.
科学领域:
- 天文学和天体物理学
- 行星科学 行星科学
背景情况:
- 环恒星积累盘对于恒星和行星的形成至关重要.
- 根据一氧化碳 (CO) 观测,人们认为围绕主序星的碎片盘是气体贫乏的,气体/尘埃比率<0.1.1.
研究的目的:
- 用分子 (H2) 观测来研究碎片盘中的气体含量.
- 重新评估碎片盘中的气体/尘埃比率,并将其与星际值进行比较.
主要方法:
- 观察到分子 (H2) 最低的旋转转移.
- 分析了贝塔图里斯,49 Ceti 和 HD135344.4 周围碎片盘的数据.
主要成果:
- 在碎片盘中检测到大量的气体.
- 计算的气体质量比基于CO的估计数量大数百到数千倍.
- 确定了与星际值 (~100) 相比的气体/尘埃比率.
结论:
- 碎片盘可以含有大量的气体,这与之前的假设相反.
- 碎片盘中大量气体的存在对正在进行的行星形成和磁盘进化有影响.
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