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arXiv 1706.03066astro-ph.EP
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关于原行星盘中多个同心环和间隙的形成

On the formation of multiple concentric rings and gaps in protoplanetary disks

Jaehan Bae, Zhaohuan Zhu, Lee Hartmann

摘要:

当气体盘中行星驱动的螺旋波变陡成激波时,它们会沉积角动量,在盘中打开一个缺口。这已经用线性理论和数值模拟进行了很好的研究,但到目前为止,只针对主旋臂--直接连接到行星上的那个。使用二维流体动力学模拟,我们表明,由行星驱动的第二和第三臂也可以打开缺口,因为他们陡峭的冲击。在低粘度盘($α= 5\times10^{-5}$)中,表面密度的第二/第三间隙的深度随着时间的推移而增长,因此即使是低质量行星(例如,超级地球或迷你海王星质量)可以打开多个可观测的间隙,只要足够的时间已经过去。将我们的结果应用于HL Tau盘,我们表明,嵌入在68.8 au(B5)环中的单个30地球质量的行星可以合理地再现13.2和32.3 au(D1和D2)的两个主要间隙的位置,并大致再现在mm连续统中看到的64.2和74.7 au(D5和D 6)的另外两个主要间隙。第二/第三间隙的位置被发现是敏感的行星质量和磁盘的温度分布,所以与精确的观测测量的温度结构的多个间隙的位置可以用来约束行星的质量。我们还评论了TW Hya和HD~163296磁盘中看到的间隙。

英文摘要:

As spiral waves driven by a planet in a gaseous disk steepen into a shock, they deposit angular momentum, opening a gap in the disk. This has been well studied using both linear theory and numerical simulations, but so far, only for the primary spiral arm -- the one directly attached to the planet. Using two-dimensional hydrodynamic simulations, we show that the secondary and tertiary arms driven by a planet can also open gaps as they steepen into shocks. The depths of the secondary/tertiary gaps in surface density grow with time in a low viscosity disk ($α= 5\times10^{-5}$), so even low-mass planets (e.g., super-Earth or mini-Neptune-mass) embedded in the disk can open multiple observable gaps, provided that sufficient time has passed. Applying our results to the HL Tau disk, we show that a single 30 Earth-mass planet embedded in the ring at 68.8~au (B5) can reasonably well reproduce the positions of the two major gaps at 13.2 and 32.3 au (D1 and D2), and roughly reproduce two other major gaps at 64.2 and 74.7 au (D5 and D6) seen in the mm continuum. The positions of secondary/tertiary gaps are found to be sensitive to the planetary mass and the disk temperature profile, so with accurate observational measurements of the temperature structure the positions of multiple gaps can be used to constrain the mass of the planet. We also comment on the gaps seen in the TW Hya and HD~163296 disk.

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。

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