AI 中文总结
本研究以嵌入型四重原恒星系统VLA1623为案例，通过N体模拟发现其8百万年内保持引力束缚四重系统的概率为30%，瓦解为三重系统的概率为25%-30%，为稳定三重（原）恒星系统的形成提供了新见解。
AI 中文摘要
高阶原恒星系统（≥3个成员）在低质量恒星形成的早期阶段被普遍观测到。恒星形成与演化领域长期存在的一个问题是，这些高阶原恒星系统会作为引力束缚系统存续下去，还是会随时间瓦解为双星系统。我们以嵌入型四重原恒星系统VLA1623及其观测约束为案例开展研究，假设成员A1、A2、B和W处于引力束缚状态。我们运用N体模拟方法，运行了一组考虑引力、原恒星吸积质量、原恒星云核存在及其消散过程的模型网格。模拟积分时长为8百万年，涵盖从原恒星阶段（0级和I级，1百万年），到前主序阶段（II级和III级，2-3百万年），再到主序阶段（4百万年）的演化过程。我们的结果显示，VLA1623从当前状态出发，在8百万年内保持为引力束缚四重系统的概率为30%；其瓦解为三重系统的概率为25%-30%。这表明，四重原恒星系统的瓦解是稳定三重（原）恒星系统形成的原因之一。成员A1和A2最有可能被弹出，而W被弹出系统的概率较低。VLA1623的稳定性取决于成员相对于主星的质量比、间距及偏心率的组合情况。
英文摘要
Higher-order protostellar systems ($\geq$3 components) are commonly observed in the early stages of low-mass star formation. A persistent question in star formation and evolution is whether these higher-order protostellar systems survive as gravitationally bound systems or dissolve into binaries over time. We explore this question with a case study of the embedded quadruple protostellar system VLA1623 and its observational constraints, assuming that the components A1, A2, B, and W are gravitationally bound. Using $N$-body simulations, we run a grid of models considering gravity, mass accretion onto protostars, the presence of the protostellar cloud core, and its dispersal. The simulations are integrated over a period of 8 Myr to take into account the evolution from the protostellar phase (Class 0 and I, 1 Myr), through the pre-main sequence (Class II and III, 2 -- 3 Myr), and into the main sequence (4 Myr). Our results show that VLA1623 has a probability of 30% to remain as a gravitationally-bound quadruple system up to 8 Myr from the current state. There is also a 25--30% probability of VLA1623 dissolving into a triple system. This suggests that the dissolution of quadruple protostellar systems contributes to the formation of stable triple (proto)stellar systems. Components A1 and A2 are the most likely to be ejected, while W has a lower probability of being ejected from the system. The stability of VLA1623 depends on a combination of component mass ratios wrt the primary, separations, and eccentricities.
Comments11 pages, 3 figures. Accepted for publication in MNRAS (Accepted 2026 August 27. Received 2026 August 27; in original form 2025 December 17)
