Protoplanetary Disk Rings as Sites for Planetesimal Formation
Protoplanetary Disk Rings as Sites for Planetesimal Formation
复制标题
原行星盘环作为小行星形成的场所
DOI：
10.3847/1538-3881/abd4d9
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
H. Klahr
中科院分区：
文献类型：
--
作者：
D. Carrera;J. Simon;Rixin Li;K. Kretke;H. Klahr
轴对称尘环是年轻的原行星盘的普遍特征。这些环很可能是由气体剖面中的压力凸起引起的；小的凸起可能会导致尘埃密度出现类似交通堵塞的模式，而大的凸起可能会完全阻止径向尘埃漂移。由此产生的尘埃浓度的增加可能会通过流动不稳定性(SI)触发小行星的形成，因为流动不稳定性本身需要一定的尘埃初始浓度。在这里，我们介绍了第一次在压力凸起存在的情况下对小行星形成的3D模拟，该压力凸起是根据阿塔卡马大毫米/亚毫米阵列所看到的。我们在一个大的3D剪切盒的中心放置了一个压力凸起，以及初始的固气比Z=0.01，我们同时考虑了粒子的反向反应和粒子的自重力。我们分别考虑毫米大小和厘米大小的粒子。对于厘米大小的粒子的模拟，我们发现即使是一个小的压力碰撞也会导致通过SI形成星子；压力碰撞不需要完全停止径向粒子漂移，SI就会变得有效。此外，通过压力碰撞中浓度的纯引力崩塌(例如，在足够高的浓度下，没有SI时会发生)不会对小行星的形成负责。对于毫米大小的粒子，我们发现了初步证据，表明没有发生小行星的形成。如果这一结果在更高的分辨率下得到证实，它可能会对小行星的形成地点施加强有力的限制。最终，我们的结果表明，对于厘米大小的粒子，压力凸起中的行星小形成是非常健壮的。
Axisymmetric dust rings are a ubiquitous feature of young protoplanetary disks. These rings are likely caused by pressure bumps in the gas profile; a small bump can induce a traffic-jam-like pattern in the dust density, while a large bump may halt radial dust drift entirely. The resulting increase in dust concentration may trigger planetesimal formation by the streaming instability (SI), as the SI itself requires some initial concentration of dust. Here we present the first 3D simulations of planetesimal formation in the presence of a pressure bump modeled specifically after those seen by Atacama Large Millimeter/submillimeter Array. We place a pressure bump at the center of a large 3D shearing box, along with an initial solid-to-gas ratio of Z = 0.01, and we include both particle back-reaction and particle self-gravity. We consider millimeter-sized and centimeter-sized particles separately. For simulations with centimeter-sized particles, we find that even a small pressure bump leads to the formation of planetesimals via the SI; a pressure bump does not need to fully halt radial particle drift for the SI to become efficient. Furthermore, pure gravitational collapse via concentration in pressure bumps (such as would occur at sufficiently high concentrations and without the SI) is not responsible for planetesimal formation. For millimeter-sized particles, we find tentative evidence that planetesimal formation does not occur. If this result is confirmed at higher resolution, it could put strong constraints on where planetesimals can form. Ultimately, our results show that for centimeter-sized particles planetesimal formation in pressure bumps is extremely robust.
影响因子：
6.5
作者：
M. Flock;J. P. Ruge;N. Dzyurkevich;T. Henning;H. Klahr;S. Wolf
通讯作者：
M. Flock;J. P. Ruge;N. Dzyurkevich;T. Henning;H. Klahr;S. Wolf
影响因子：
7.9
作者：
Andrews, Sean M.;Huang, Jane;Ricci, Luca
通讯作者：
Ricci, Luca