AI 中文总结
研究双星系统中盘的密度结构对尘埃增长的影响，通过流体动力学模拟探索伴星轨道，发现环绕双星盘内尘埃增长受扰，最大颗粒尺寸变小，而环绕恒星盘颗粒尺寸与孤立盘相似，大双星环绕双星盘行星形成具挑战性。
AI 中文摘要
恒星的多重性改变了原行星盘的密度结构，进而改变了行星形成的初始条件。然而，伴星盘相互作用与尘埃增长之间的相互作用仍知之甚少。这项工作的目标是研究与伴星发生潮汐相互作用的盘的密度结构在多大程度上促进或抑制尘埃颗粒的增长。我们对围绕双星中一颗或两颗恒星运行的原行星盘进行了一组流体动力学模拟，包括尘埃增长和破碎。我们探索了一系列伴星轨道，并将结果与单星参考案例进行比较。我们发现尘埃增长主要由尘埃的局部堆积驱动。在环绕双星盘中，最大颗粒尺寸比孤立盘中小多达五倍。这一结果可能源于内部双星引起的扰动，它阻止了尘埃颗粒的正常沉降和漂移。因此，由流不稳定驱动的强烈聚集所需的条件难以实现。相比之下，双星系统中的环绕恒星盘表现出与孤立盘中相似的颗粒尺寸，导致由流不稳定引起强烈聚集的条件相当。在拥有大于几个天文单位的双星的环绕双星盘中，通过核心吸积形成行星似乎具有挑战性，这表明在动态稳定极限附近观测到的环绕双星行星并非原位形成。相反，与孤立系统相比，外部伴星的扰动对密度驱动的尘埃增长影响很小。
英文摘要
Stellar multiplicity alters the density structure of protoplanetary discs and thereby the initial conditions for planet formation. Yet, the interplay between companion-disc interactions and dust growth remains poorly understood. The goal of this work is to investigate to what extent the density structure of a disc undergoing tidal interactions with a companion star promotes or inhibits the growth of dust grains. We perform a set of hydrodynamical simulations of protoplanetary discs orbiting one or both stars of a binary, including dust growth and fragmentation. We explore a range of companion orbits and compare the results with a single-star reference case. We find that dust growth is mainly driven by local accumulations of dust. In circumbinary discs, the maximum grain size is up to five times smaller than in isolated discs. This result likely originates from the perturbations caused by the inner binary, which prevent dust grains from properly settling and drifting. As a consequence, the conditions required to trigger strong clumping driven by the streaming instability are difficult to achieve. In contrast, circumstellar discs in binary systems exhibit grain sizes similar to those in isolated discs, leading to comparable conditions for strong clumping by the streaming instability. Planet formation through core accretion seems challenging in circumbinary discs harbouring binaries larger than a few au, suggesting that circumbinary planets observed near the dynamical stability limit did not form in situ. Conversely, perturbations from external companions only marginally affect density-driven dust growth compared to isolated systems.
CommentsAccepted for publication in A&A, 17 pages, 11 figures
