Influence of general-relativity effects, dynamical tides, and collisions on planet-planet scattering close to the star
Influence of general-relativity effects, dynamical tides, and collisions on planet-planet scattering close to the star
复制标题
广义相对论效应、动力潮汐和碰撞对靠近恒星的行星间散射的影响
DOI：
10.1051/0004-6361/201935065
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发表时间：
2019
影响因子：
6.5
通讯作者：
Nagasawa M.
中科院分区：
文献类型：
--
作者：
Marzari F.;Nagasawa M.
行星-行星（P-P）散射是产生偏心系外行星的一种有效且稳健的动力学机制。加上与中心恒星的潮汐相互作用，这种现象也可以解释在圆形和潜在的错位轨道上的近距离巨行星。目的：我们探索发生在恒星附近的散射事件，并测试它们是否能再现在紧密轨道上观测到的巨大系外行星轨道分布的主要特征。在我们的建模中，我们利用了一个基于Hermite算法的数值积分代码，并考虑了广义相对论、动态潮汐和两体碰撞的影响。结果我们发现P-P散射事件发生在三颗巨行星最初在靠近恒星的圆形轨道上运动的系统中，产生了类似于目前观察到的行星群，包括偏心和错位的近距离行星。潮汐和广义相对论的贡献在确定混沌相位的最终结果方面是相关的。结论如果三颗行星在靠近其恒星的轨道上交叉时，两体碰撞主导了混沌演化，那么最终的分布表明有相当数量的行星处于偏心轨道上。高度错位的近距离巨行星是由内行星的初始半长轴在0.2 au左右或更大的系统产生的。
ContextPlanet–planet (P–P) scattering is an efficient and robust dynamical mechanism for producing eccentric exoplanets. Coupled to tidal interactions with the central star, this phenomenon can also explain close-in giant planets on circularized and potentially misaligned orbits.AimsWe explore scattering events occurring close to the star and test if they can reproduce the main features of the observed orbital distribution of giant exoplanets on tight orbits.MethodsIn our modeling we exploited a numerical integration code based on the Hermite algorithm and including the effects of general relativity, dynamical tides, and two-body collisions.ResultsWe find that P–P scattering events occurring in systems with three giant planets initially moving on circular orbits close to their star produce a population of planets similar to that presently observed, including eccentric and misaligned close-in planets. The contribution of tides and general relativity is relevant in determining the final outcome of the chaotic phase.ConclusionsEven if two-body collisions dominate the chaotic evolution of three planets in crossing orbits close to their star, the final distribution shows a significant number of planets on eccentric orbits. The highly misaligned close-in giant planets are instead produced by systems where the initial semimajor axis of the inner planet was around 0.2 au or beyond.