论文标题
流媒体不稳定性后的生长：行星生长的径向距离依赖性
Growth after the streaming instability: The radial distance dependence of the planetary growth
论文作者
论文摘要
假设流媒体不稳定性是在特定的原始磁盘位置触发的，在特定的原球磁盘位置，固体颗粒的体积密度与气体的体积密度富集。因此，当局部满足这种情况时，会形成一个行星环。这些行星相互碰撞，并从外盘向内移动卵石以进一步增加质量。我们研究了在各种磁盘半径下在环皮带中形成的地球的生长。它们的初始质量分布是根据从流不稳定模拟中汇总的公式来计算的。我们使用基于最小质量太阳星云（MMSN）或Toomre稳定性标准的原星盘模型模拟了行星模型的随后动力学演变。对于MMSN型号，卵石积聚和行星的积聚均有效，近距离为0.3 $ au，导致出现了$ 1 $ MYR后出现了几个超级地球行星。为了进行比较，只有最大的行星在出生时出生于$ r {=} 3 $ au，而行星的出生时会经历大量的质量增长，而行星的质量为$ r {=} 30 $ au的体验很少或没有增长。另一方面，在浓密的Toomre磁盘中，最大的形成行星可以以$ t {=} 1 $ MYR到达地球质量，并在Neptune和Saturn的质量上达到$ 3 $ MYR之间的质量，价格为$ 30 $ AU和$ 100 $ au。卵石和行星的积聚率都随盘径向距离而降低。然而，在更遥远的磁盘区域，行星的吸积比卵石积聚不那么明显。综上所述，当磁盘具有更高的气体密度，较高的卵石通量和/或较低的卵石数量时，行星会获得更高的质量。
Streaming instability is hypothesized to be triggered at particular protoplanetary disk locations where the volume density of the solid particles is enriched comparable to that of the gas. A ring of planetesimals thus forms when this condition is fulfilled locally. These planetesimals collide with each other and accrete inward drifting pebbles from the outer disk to further increase masses. We investigate the growth of the planetesimals that form in a ring-belt at various disk radii. Their initial mass distributions are calculated based on the formula summarized from the streaming instability simulations. We simulate the subsequent dynamical evolution of the planetesimals with a protoplanetary disk model based either on the minimum mass solar nebula (MMSN) or on the Toomre stability criterion. For the MMSN model, both pebble accretion and planetesimal accretion are efficient at a close-in orbit of $0.3$ AU, resulting in the emergence of several super-Earth mass planets after $1$ Myr. For comparison, only the most massive planetesimals undergo substantial mass growth when they are born at $r{=}3$ AU, while the planetesimals at $r{=}30$ AU experience little or no growth. On the other hand, in the denser Toomre disk, the most massive forming planets can reach Earth mass at $t{=}1$ Myr and reach a mass between that of Neptune and that of Saturn within $3$ Myr at $30$ AU and $100$ AU. Both the pebble and planetesimal accretion rate decrease with disk radial distance. Nevertheless, planetesimal accretion is less pronounced than pebble accretion at more distant disk regions. Taken together, the planets acquire higher masses when the disk has a higher gas density, a higher pebble flux, and/or a lower Stokes number of pebbles.
