AI 中文总结
研究晚期吸积盘中星子与行星形成及子结构出现，用耦合多方面的综合建模框架，发现丰富尘埃供应等能使巨行星快速形成，其产生的子结构促进多代星子形成，为行星系统相关问题提供新视角。
AI 中文摘要
晚期吸积可补充原行星盘中行星的构成物质并显著改变其结构演化。由此产生的压力峰有效聚集尘埃、促进颗粒凝聚并通过流不稳定触发星子形成。本文研究晚期吸积盘中星子与行星形成的可能性以及可观测子结构的出现。利用耦合尘埃凝聚与动力学、星子形成、N体引力、行星生长及行星-盘相互作用的综合建模框架。结果表明，丰富的尘埃供应和下落气体形成的迁移屏障能使气体巨行星在百万年内通过卵石和气体吸积快速形成，即便在大轨道距离（约70天文单位）。这些巨行星反过来施加扭矩产生多个次级盘状子结构，促进多代星子形成并导致多样的行星系统构型。星子表现出由其形成时期和环境决定的独特动力学特性，类似于外太阳系中的小天体群体。在合成的1.3毫米连续谱观测中，吸积和行星诱导的子结构都清晰可见，与阿塔卡马大型毫米/亚毫米波阵列（ALMA）勘测中检测到的多环盘非常相似。我们的模型为遥远巨行星的起源、持久的星子形成以及具有多个子结构的盘的普遍存在提供了新视角。
英文摘要
Late infall can replenish the building materials of planets in protoplanetary disks and dramatically alter their structural evolution. The resulting pressure bumps effectively accumulate dust, facilitate grain coagulation, and trigger planetesimal formation via the streaming instability. In this work, we investigated the potential for planetesimal and planet formation, as well as the emergence of observable substructures, in disks undergoing late-stage infall. We utilized a comprehensive modeling framework that couples dust coagulation and dynamics, planetesimal formation, N-body gravity, planetary growth, and planet-disk interactions. Our results show that the abundant dust supply and the migration barrier created by the infalling gas enable the rapid formation of gas giants via pebble and gas accretion within one million years, even at large orbital distances (~70 au). These giants, in turn, exert torques that generate multiple secondary disk substructures, fostering multigenerational planetesimal formation and resulting in diverse planetary system configurations. The planetesimals exhibit distinct dynamical properties that are determined by their formation epoch and environment, which are analogous to the small-body populations in the outer Solar System. Both the infall- and planet-induced substructures are clearly visible in synthetic 1.3-mm continuum observations, closely resembling the multi-ring disks detected in ALMA surveys. Our model provides a new perspective on the origin of distant giant planets, long-lasting planetesimal formation, and the prevalence of disks with multiple substructures.
Comments18 pages, 9 figures, accepted for publication in A&A; revised following language editing by A&A
