论文标题

在I型迁移的背景下,平均运动共振捕获

Mean motion resonance capture in the context of type-I migration

论文作者

Kajtazi, Kaltrina, Petit, Antoine C., Johansen, Anders

论文摘要

捕获成平均运动共振(MMR)是重要的动力学机制,因为它塑造了行星系统的最终结构。我们模拟了经过迁移的两个或三个行星的系统,这些系统具有不同的初始参数,例如行星质量和磁盘表面密度,并分析所得的谐振链。与以前的研究相反,我们的结果表明,磁盘性能对捕获中的捕获具有主要影响,而总行星质量几乎不会影响最终系统构型,只要行星不打开磁盘中的空隙即可。我们确认绝热谐振捕获是了解导致MMR形成的条件的正确框架,因为其预测在质量上与数值结果相似。但是,我们发现偏心阻尼可以促进给定共振中的捕获。我们发现,在典型的磁盘条件下,行星倾向于将行星捕获到2:1或3:2 mmrs中,这与观察到的系外行星MMR非常吻合。我们的结果预测了两类系统:那些具有均匀共振(2:1或3:2 mmr)的链链的系统,而内部对的内部对(例如4:3:2链)具有更紧凑的内对。观察到的系外行星系统中都存在两类共鸣链。另一方面,内部对比外部链的链条更罕见,并且从随机捕获中出现。我们在这里的工作可用于将外部系统的当前配置链接到Protoplanetary磁盘中的形成条件。

Capture into mean motion resonance (MMR) is an important dynamical mechanism as it shapes the final architecture of a planetary system. We simulate systems of two or three planets undergoing migration with varied initial parameters such as planetary mass and disk surface density and analyse the resulting resonant chains. In contrast to previous studies, our results show that the disk properties have the dominant impact on capture into mean motion resonance, while the total planetary mass barely affects the final system configuration as long as the planet does not open a gap in the disk. We confirm that the adiabatic resonant capture is the correct framework to understand the conditions leading to MMR formation, since its predictions are qualitatively similar to the numerical results. However, we find that the eccentricity damping can facilitate the capture in a given resonance. We find that under typical disk conditions, planets tend to be captured into 2:1 or 3:2 MMRs, which agrees well with the observed exoplanet MMRs. Our results predict two categories of systems: those that have uniform chains of wide resonances (2:1 or 3:2 MMRs) and those that have a more compact inner pair than the outer pair such as 4:3:2 chains. Both categories of resonant chains are present in observed exoplanet systems. On the other hand, chains with a wider inner pair than the outer one are very rare and emerge from stochastic capture. Our work here can be used to link current configuration of exoplanetary systems to the formation conditions within protoplanetary disks.

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