arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2104.02664astro-ph.EPastro-ph.SR
收藏

通过卵石吸积和迁移建立伽利略卫星系统:一个原始的共振链

Building the Galilean moons system via pebble accretion and migration: A primordial resonant chain

Gustavo Madeira, André Izidoro, Silvia M. Giuliatti Winter

摘要:

伽利略卫星的起源-即木卫一,木卫二,木卫三和木卫四-还没有完全了解。在这里,我们使用N体数值模拟研究伽利略卫星的形成在木星周围的气体环行星盘。我们的模型包括卵石的增长,气体驱动的迁移,气体潮汐阻尼和阻力的影响。在我们的模拟中,小卫星首先通过卵石吸积生长,并开始向内迁移。当它们到达盘内边缘的陷阱时,发生散射事件和碰撞,促进额外的生长。成长中的卫星最终会达到一个多共振的结构,固定在圆盘的内边缘。我们最好的伽利略卫星的质量匹配是在模拟中产生的集成卵石通量是1 e-3兆焦耳。这些模拟通常产生3到5颗卫星。在我们最好的模拟中,相邻的卫星对都锁定在2:1的平均运动共振中。然而,它们也有适度的偏心轨道(0.1),不像目前的真正的卫星。我们认为伽利略卫星系统是一个原始的共振链,类似于TRAPPIST-1,开普勒-223和TOI-178等系外行星系统。木卫四可能在过去与木卫三共振,但离开了这个配置-没有打破拉普拉斯共振-通过发散迁移由于潮汐行星卫星相互作用。这些同样的影响进一步将这些卫星的轨道偏心率降低到目前的值(0.001)。我们的研究结果支持这一假设,木卫一和木卫二出生时富含水冰成分,后来失去了所有/大部分的水。对伽利略卫星原始组成的严格限制对于区分形成模型至关重要。

英文摘要:

The origins of the Galilean satellites - namely Io, Europa, Ganymede, and Callisto - is not fully understood yet. Here we use N-body numerical simulations to study the formation of Galilean satellites in a gaseous circumplanetary disk around Jupiter. Our model includes the effects of pebble accretion, gas-driven migration, and gas tidal damping and drag. Satellitesimals in our simulations first grow via pebble accretion and start to migrate inwards. When they reach the trap at the disk inner edge, scattering events and collisions take place promoting additional growth. Growing satellites eventually reach a multi-resonant configuration anchored at the disk inner edge. Our best match to the masses of the Galilean satellites is produced in simulations where the integrated pebble flux is 1e-3 MJ. These simulations typically produce between 3 and 5 satellites. In our best analogues, adjacent satellite pairs are all locked in 2:1 mean motion resonances. However, they have also moderately eccentric orbits (0.1), unlike the current real satellites. We propose that the Galilean satellites system is a primordial resonant chain, similar to exoplanet systems as TRAPPIST-1, Kepler-223, and TOI-178. Callisto was probably in resonance with Ganymede in the past but left this configuration - without breaking the Laplacian resonance - via divergent migration due to tidal planet-satellite interactions. These same effects further damped the orbital eccentricities of these satellites down to their current values (0.001). Our results support the hypothesis that Io and Europa were born with water-ice rich compositions and lost all/most of their water afterwards. Firmer constraints on the primordial compositions of the Galilean satellites are crucial to distinguish formation models.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑