标题： 尘埃环将具有偏心轨道的原行星困住并被它们消耗掉 显示英文标题

标题： Dust rings trap protoplanets on eccentric orbits and get consumed by them

摘要： 我们使用三维数值模拟，采用双流体模型和嵌套网格，研究质量为$M \in [0.1-8]$~M$_\oplus$的原行星在尘埃环附近的轨道演化和质量增长。 我们发现两种稳定的椭圆轨道，使行星锁定在环附近，从而抑制其迁移并允许其从环中吸积尘埃。 其中一种轨道的偏心率与气体盘的纵横比相当，并且其近日点位于环内，使得每次经过时都能间歇性吸积。 另一种轨道的偏心率较小，远日点略微位于环内。 被锁定在外部轨道的行星能有效从环中吸积，并在时间尺度$\gtrsim 10^5$ yr（对于10~M$_\oplus$的尘埃环位于10~au）内达到 runaway 气体吸积的关键质量，而被锁定在内部轨道的行星增长较慢，在盘寿命内可能无法超越超级地球阶段。 虽然在我们的模拟中，形成于环内的低质量胚胎最终会进入外部轨道，但路径可能取决于环的具体细节。 在外部轨道上的捕获是由于每次穿过环时产生的间歇性强热力，此时吸积率会激增。 这种捕获对困扰考虑环内圆形轨道上被捕获行星的模型中的不确定性不敏感。 它非常稳健，可能允许成长中的行星沿着扩展的环移动很远的距离。 显示英文摘要

摘要： We study the orbital evolution and mass growth of protoplanets with masses $M \in [0.1-8]$~M$_\oplus$ in the vicinity of a dusty ring, using three-dimensional numerical simulations with a two-fluid model and nested-meshes. We find two stable, eccentric orbits that lock the planet in the ring vicinity, thereby inhibiting its migration and allowing it to accrete dust from the ring. One of these orbits has an eccentricity comparable to the aspect ratio of the gaseous disc and has its periastron within the ring, enabling intermittent accretion during each pass. The other orbit has a smaller eccentricity and an apoastron slightly inside the ring. A planet locked at the outer orbit efficiently accretes from the ring and can reach the critical mass for runaway gas accretion on timescales $\gtrsim 10^5$ yr (for a 10~M$_\oplus$ dust ring at 10~au) while a planet locked at the inner orbit has a slower growth and might not supersede the super-Earth stage over the disc lifetime. While in our runs a low-mass embryo forming within the ring eventually joins the outer orbit, it is likely that the path taken depends on the specific details of the ring. The trapping on the outer orbit arises from an intermittent, strong thermal force at each passage through the ring, where the accretion rate spikes. It is insensitive to uncertainties that plague models considering planets trapped on circular orbits in rings. It is highly robust and could allow a growing planet to follow an expanding ring over large distances.