Structure and evolution models for Uranus, Neptune, and extrasolar planets with observed Love number k2

天王星、海王星和太阳系外行星的结构和演化模型（观测到的爱数 k2）

• 批准号: 329337209
• 负责人: Dr. Nicola Tosi, since 7/2022
• 金额: --
• 依托单位: Institut für Planetenforschung
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2017
• 资助国家: 德国
• 起止时间: 2016-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/329337209?language=en
• 关键词: Structure; evolution; models; Uranus; Neptune

Observational exoplanet surveys suggest that planets in the size range of 1.7 to 4.0 Earth radii are the most abundant planets in the Solar neighborhood. Since the ice giants Uranus and Neptune are our solar system representatives for this class of planets, we label them collectively Neptune-like. The proposed work aims to understand the internal structure and evolution of Neptune-like planets. Parameters of interest in this regard are the luminosity of Uranus and Neptune and the Love number k2 of extrasolar planets. We will investigate how internal redistribution of elements of the HCNO complex due to demixing or partitioning affects the luminosity of the cool ice giants Uranus and Neptune. These planets are not homogeneous, perhaps due to such redistribution or because of the formation process. We will investigate if stable stratification with conductive heat transport can occur as a result of the significant conductivity of water in the deep interior and across the compositional gradient zones as indicated by the gravity field. For that purpose we rely on predictions on the structural properties and equation of state data from experiments and simulations of water, ammonia, methane, hydrogen, and their mixtures where available, e.g. from SP3 and SP9. Furthermore, we will develop structure models of extrasolar planets with measured Love number k2 from SP6. While the tidal potential field deformation (k2) is accessible by measurements of radial velocity (RV) and transit timing (TT) variations, the shape deformation (h2) is accessible by transit light curve (TLC) analysis. We will investigate if the relation h2=1+k2 as known in the limit of spherical objects is still applicable if the planet is exposed to strong tidal forcing, as will be the case for those exoplanets for which k2 and h2 can be measured.

观测的系外行星调查表明，在1.7至4.0地球半径范围内的行星是太阳系附近最丰富的行星。由于冰巨人天王星和海王星是我们太阳系这类行星的代表，我们将它们统称为海王星。这项工作旨在了解海王星类行星的内部结构和演化。在这方面的兴趣参数是天王星和海王星的光度和爱数k2的太阳系外行星。我们将研究如何内部重新分配的元素的HCNO复杂的分层或分区影响的亮度冷冰巨人天王星和海王星。这些行星并不均匀，也许是由于这种重新分配或形成过程。我们将调查，如果稳定的分层与传导热传输可以发生作为一个结果的水的显着导电性在深内部和整个组成梯度区所示的重力场。为此，我们依赖于对水、氨、甲烷、氢及其混合物（如SP3和SP9）的实验和模拟的结构特性和状态方程数据的预测。此外，我们将开发太阳系外行星的结构模型与测量的爱数k2从SP6。虽然潮汐势场变形（k2）可通过测量径向速度（RV）和过境时间（TT）的变化，形状变形（h2）可通过过境光曲线（TLC）分析。我们将研究如果行星受到强潮汐力的作用，那么在球形物体的极限中已知的关系式h2=1+k2是否仍然适用，对于那些可以测量k2和h2的系外行星来说也是如此。