类似太阳的恒星中增强的耗尽,这些恒星的轨道上有行星
Garik Israelian1, Elisa Delgado Mena, Nuno C Santos
1Instituto de Astrofisíca de Canarias, Via Láctea s/n, E-38200 La Laguna, Spain. gil@iac.es
Nature
|November 13, 2009
概括
与没有行星的恒星相比,拥有行星的恒星显示出大量耗尽的 (Li). 这表明行星可能会影响恒星内部,促进燃烧和耗尽.
科学领域:
- 天文学和天体物理学
- 恒星进化 恒星进化
- 外系行星科学 外系行星科学
背景情况:
- 太阳表面的 (Li) 含量明显低于太阳前太阳的含量.
- 在太阳型恒星中观察到的丰度变化很难从理论上解释.
- 之前的研究表明行星与耗尽之间存在联系,但缺乏强大的比较小组.
研究的目的:
- 为了研究行星的存在和太阳类恒星中的表面丰度之间的关系.
- 为了确定带有行星的恒星与没有行星的恒星相比,是否表现出不同的耗耗水平.
主要方法:
- 在对太阳类恒星的无偏样本中分析了的丰度.
- 在有或没有被探测到的行星的恒星之间比较的丰度.
- 使用光谱分析测量表面含量.
主要成果:
- 发现了行星的恒星显示出极低的丰度,不到原始水平的1%.
- 大约50%的没有被探测到行星的恒星保留了显著更高的丰度 (大约是耗尽值的10倍).
- 在行星宿主和非行星宿主太阳同类物之间观察到一个明确的耗差异.
结论:
- 行星的存在似乎与恒星中耗尽的增强有很强的相关性.
- 行星的影响可能会加深恒星对流区,促进的燃烧和耗尽.
- 这一发现为太阳型恒星中观察到的丰度范围提供了潜在的解释.
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