2356965

Target RA (J2000): 145.827866 and deg Target Dec (J2000): 15.00436 and deg Gaia GMag: 10.5 Programme ID: CH_PR140068 Programme Manager: EGGER PI of observing programme: Benz Title of programme: Axis 1 - Constraining the abundance of water in hot planets (HotWatermelon) Abstract: Planets located close enough to their star experience evaporation which leads to a dichotomy in the possible gas content of these objects. These planets either contain more than around one percent of gas (in mass) or no gas at all (see Owen and Wu 2017). This dichotomy when expressed in term of mass-radius relation implies the existence of a region in the mass-radius diagram of hot planets where dry planets cannot exist. We propose to observe planets that could lie in this region with CHEOPS. Combining a precise radius and mass will allow us to identify planets in this forbidden region hence showing that they have to contain volatiles most likely water. Our data combined with future JWST observations will also constrain the efficiency of evaporation. [truncated! Please see actual data for full text]

目标赤经（RA, J2000）：145.827866度
目标赤纬（Dec, J2000）：15.00436度
盖亚G星等（Gaia GMag）：10.5
项目ID：CH_PR140068
项目主管：EGGER
观测项目首席研究员（PI）：Benz
项目标题：Axis 1——约束热行星中水的丰度（HotWatermelon）
摘要：距离恒星足够近的行星会发生蒸发，这导致这些天体的可能气体含量出现二分性。这些行星要么含有超过约1%（质量占比）的气体，要么完全不含气体（参见Owen和Wu 2017）。这种二分性在质量-半径关系中体现为：热行星的质量-半径图中存在一个干燥行星无法存在的区域。我们提议使用CHEOPS观测可能位于该区域的行星。结合精确的半径和质量数据，我们能够识别出处于这一禁区的行星，进而证明它们必须含有挥发性物质（最可能为水）。我们的数据与未来詹姆斯·韦伯太空望远镜（JWST）的观测结果相结合，还将约束蒸发的效率。[截断！请查阅实际数据获取全文]