海洋行星还是厚层大气：关于有厚层大气的固态系外行星的质量-半径关系
Ocean Planet or Thick Atmosphere: On the Mass-Radius Relationship for Solid Exoplanets with Massive Atmospheres
摘要：
一颗系外行星的整体组成通常是从它的平均密度推断出来的。然而，对于小行星来说，平均密度在组成范围内并不是唯一的。一些重要的行星参数的变化--这些参数很难或不可能单独通过测量来约束--产生了平均密度相同但体积组成差异很大的行星。我们发现，增加一个相当于固体行星质量0.1%-10%的气体包层，会导致半径增加5-60%。一颗具有一定质量和半径的行星可能含有大量的水冰（所谓的海洋行星），或者有一个大的岩石铁核和一些H和/或He。例如，GJ 436 b的半径可以用各种各样的成分来解释，尽管所有的模型都需要一些H/He。我们的结论是，水世界的识别的基础上的质量半径的关系是不可能的，除非一个显着的气体层可以通过其他手段排除。
英文摘要：
The bulk composition of an exoplanet is commonly inferred from its average density. For small planets, however, the average density is not unique within the range of compositions. Variations of a number of important planetary parameters--which are difficult or impossible to constrain from measurements alone--produce planets with the same average densities but widely varying bulk compositions. We find that adding a gas envelope equivalent to 0.1%-10% of the mass of a solid planet causes the radius to increase 5-60% above its gas-free value. A planet with a given mass and radius might have substantial water ice content (a so-called ocean planet) or alternatively a large rocky-iron core and some H and/or He. For example, a wide variety of compositions can explain the observed radius of GJ 436b, although all models require some H/He. We conclude that the identification of water worlds based on the mass-radius relationship alone is impossible unless a significant gas layer can be ruled out by other means.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
