论文标题
在没有气体巨人的系统中,在N体模拟中具有破碎的水域
Water worlds in N-body simulations with fragmentation in systems without gaseous giants
论文作者
论文摘要
我们分析了在没有气态巨人的情况下,分析了太阳型恒星周围陆地状行星的形成和演变。特别是,我们专注于在系统可居住区(Hz)中生存的人的物理和动力学特性。这项研究基于N体模拟之间的比较研究,该研究包括碎裂和其他将所有碰撞视为完美合并的其他研究。我们使用了上一篇论文中介绍的N体代码,该代码允许行星碎片化。我们为400 MYR进行了三组24套模拟。开发了两组,采用了一个模型,其中包括撞击碰撞和行星碎片,每个模型都有不同的最小值值允许碎片的质量。对于第三组,我们认为所有碰撞都会导致完美的合并。在N体模拟中产生的系统有和没有碎片化的系统非常相似,并且存在一些差异。在碎裂的运行中,形成的行星的质量较低,因为部分分布在碰撞碎片之间。此外,这些行星的偏心率较低,大概是由于生成的片段的动态摩擦。完美的合并和撞车碰撞是最常见的结果。无论采用碰撞处理如何,在HZ中生存的大多数行星都会在雪线以外的模拟开始,最终水含量很高。碎片对质量和水含量的贡献可以忽略不计。最后,碎片的最小质量可能在行星的碰撞历史中起重要作用。结合碎片化和撞击碰撞的碰撞模型导致对形成的类似陆生状行星的物理特性的更详细描述。我们得出的结论是,行星碎裂并不是Hz中水世界形成的障碍。
We analyze the formation and evolution of terrestrial-like planets around solar-type stars in the absence of gaseous giants. In particular, we focus on the physical and dynamical properties of those that survive in the system's Habitable Zone (HZ). This study is based on a comparative study between N-body simulations that include fragmentation and others that consider all collisions as perfect mergers. We use an N-body code, presented in a previous paper, that allows planetary fragmentation. We carry out three sets of 24 simulations for 400 Myr. Two sets are developed adopting a model that includes hit-and-run collisions and planetary fragmentation, each one with different values of the individual minimum mass allowed for the fragments. For the third set, we considered that all collisions lead to perfect mergers. The systems produced in N-body simulations with and without fragmentation are broadly similar, with some differences. In runs with fragmentation, the formed planets have lower masses since part it is distributed amongst collisional fragments. Additionally, those planets presented lower eccentricities, presumably due to dynamical friction with the generated fragments. Perfect mergers and hit-and-run collisions are the most common outcome. Regardless of the collisional treatment adopted, most of the planets that survive in the HZ start the simulation beyond the snow line, having very high final water contents. The fragments' contribution to their mass and water content is negligible. Finally, the individual minimum mass for fragments may play an important role in the planets' collisional history. Collisional models that incorporate fragmentation and hit-and-run collisions lead to a more detailed description of the physical properties of the terrestrial-like planets formed. We conclude that planetary fragmentation is not a barrier to the formation of water worlds in the HZ.