[P-AE18] 系外惑星

[PAE18-18] Formation of super-Earths: effects of water enrichment and partitioning

★Invited Papers

*木村 真博^1,2、Tim Lichtenberg² (1.東京大学　大学院理学系研究科附属宇宙惑星科学機構、2.フローニンゲン大学)

キーワード：super-Earth/sub-Neptune、primordial atmosphere、planet formation

Super-Earths and sub-Neptunes are among the most common types of exoplanets discovered to date, yet their formation and atmospheric evolution remain poorly understood. The formation of primordial atmospheres on these planets is a critical area of study in understanding the diversity and evolution of exoplanetary systems. This talk explores the mechanisms by which these atmospheres form, with a particular focus on the role of water enrichment and its partitioning between the interior and the atmosphere. We discuss how the accretion of volatile-rich planetesimals and chemical reaction between the atmosphere and magma ocean, as well as the partitioning of water, contribute to the atmospheric properties. By integrating insights from planetary formation models and primordial atmospheric formation and evolution, this talk aims to provide a comprehensive understanding of how water-rich super-Earths and sub-Neptunes acquire and maintain their primordial atmospheres and to give implications for the ongoing and near-future observations.