论文标题
通过卵石积聚和行星 - 地球碰撞促进了多个遥远的巨型行星的质量增长
Promoted Mass Growth of Multiple, Distant Giant Planets through Pebble Accretion and Planet-Planet Collision
论文作者
论文摘要
我们提出了一个卵石驱动的行星形成场景，以在早期气盘相中形成具有较高多重性和较大轨道距离的巨型行星。我们执行N体模拟，以研究磁盘中低质量原子星形的生长和迁移，并具有内部粘性和外部恒星辐照区域的生长和迁移。该模型的关键特征是，巨型行星岩心通过卵石积聚和行星 - 星空碰撞的结合迅速生长。因此，这加快了他们的汽油积聚。由于有效的生长，行星从快速I型迁移到较慢的II型迁移较早迁移，从而大大降低了内向迁移。多个巨型行星可以以这种方式依次形成半圆形轴。与单个行星生长相比，考虑到大量的原始星网，质量生长和轨道保留更加明显。最终，几个巨型行星形成，轨道距离在$ 1.5 { - } 3 $ MYR之后，轨道距离为几十至几十个AU。所得的模拟行星种群可以与磁盘观测中表现出的子结构以及在径向速度和微透镜调查中观察到的大轨道距离系外行星。
We propose a pebble-driven planet formation scenario to form giant planets with high multiplicity and large orbital distances in the early gas disk phase. We perform N-body simulations to investigate the growth and migration of low-mass protoplanets in the disk with inner viscously heated and outer stellar irradiated regions. The key feature of this model is that the giant planet cores grow rapidly by a combination of pebble accretion and planet-planet collisions. This consequently speeds up their gas accretion. Because of efficient growth, the planet transitions from rapid type I migration to slow type II migration early, reducing the inward migration substantially. Multiple giant planets can sequentially form in this way with increasing semimajor axes. Both mass growth and orbital retention are more pronounced when a large number of protoplanets are taken into account compared to the case of single planet growth. Eventually, a few numbers of giant planets form with orbital distances of a few to a few tens of AUs within $1.5{-}3$ Myr after the birth of the protoplanets. The resulting simulated planet populations could be linked to the substructures exhibited in disk observations as well as large orbital distance exoplanets observed in radial velocity and microlensing surveys.
