发表机构
IRAP, Université de Toulouse, CNRS, CNES; Leibniz-Institut für Astrophysik Potsdam (AIP); IPAG, Université Grenoble Alpes, CNRS; Departamento de Física, Universidad de Santiago de Chile; Department of Physics and Astronomy, University of Nevada, Las Vegas; Max Planck Institut für Astronomie; Department of Physics, University of Warwick; Université Claude Bernard Lyon 1, ENS de Lyon, CNRS, CRAL; School of Physics and Astronomy, University of Leicester（图卢兹大学 IRAP; 波茨坦莱布尼茨天体物理研究所; 格勒诺布尔阿尔卑斯大学 IPAG; 圣地亚哥智利大学物理系; 内华达大学拉斯维加斯分校物理与天文系; 马克斯·普朗克天文学研究所; 沃里克大学物理系; 里昂第一大学、里昂高等师范学校 CRAL; 莱斯特大学物理与天文学院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过二维流体动力学模拟和辐射转移计算，发现晚期吸积触发的引力不稳定性在原行星盘中形成旋臂，其耗散产生持久尘埃环，使盘从旋臂结构演化为环状结构。
AI 中文摘要
亚结构似乎是所有延展原行星盘的普遍特征。它们尤其出现在仍被周围、可能正在吸积的物质所包围的盘中。在本研究中，我们重新审视了引力不稳定性（GI）在原行星盘尘埃和气体辐射中的观测特征。我们重点关注经历短暂晚期吸积事件、通过GI触发旋臂的盘，以研究毫米级尘埃的长期动力学。我们进行了二维流体动力学模拟，模拟了自引力盘中的气体和毫米级尘埃，并对恒星辐照和吸积进行了简化处理。结果通过三维辐射转移计算进行后处理。在吸积期间，GI启动，盘发展出以旋臂持续形成为特征的引力湍动状态。吸积结束后不久，毫米级尘埃仍与气体良好耦合，尘埃辐射在近红外散射光和连续谱辐射中均表现出大尺度旋臂。即使在吸积停止很久之后，双旋臂仍由GI在盘的特定区域持续激发。它们的耗散导致多个持久压力极大值的形成，这些可被视为旋臂激波的遗迹。它们形成持久的尘埃环，这些环或多或少是轴对称的。因此，一旦晚期吸积结束，大质量盘可以逐渐从具有连续谱旋臂的盘演化为具有多个、可能不对称的明亮连续谱环的盘。在近红外散射光中，盘在吸积期间或吸积停止后不久最初显示多条旋臂，最终显示多个环。然而，旋臂的持续激发意味着，从谱线辐射导出的残余视线速度在盘上显示出大尺度旋臂。
英文摘要
Substructures appear to be a common trait of all extended protoplanetary discs. They are found notably in discs still surrounded by ambient, possibly infalling material. In this study, we revisit the observational signatures of gravitational instability (GI) in the dust and gas emission of protoplanetary discs. We focus on discs undergoing a short-lived episode of late infall that triggers spirals via GI, in order to investigate the long-term dynamics of millimetre-sized dust. We performed 2D hydrodynamical simulations modelling gas and millimetre-sized dust in a self-gravitating disc, with a simplified treatment of stellar irradiation and infall. Results were post-processed by 3D radiative transfer calculations. During infall, GI sets in and the disc develops a gravitoturbulent state characterised by the continuous formation of spirals. Shortly after infall ends, the millimetre-sized dust remains well coupled to the gas, and the dust emission exhibits large-scale spirals in both near-infrared scattered light and continuum emission. Even long after infall has ceased, two-armed spirals are persistently excited by GI in specific regions of the disc. Their dissipation entails the formation of multiple long-lasting pressure maxima, which can be viewed as vestiges of shocks induced by the spirals. They form persistent dust rings that are more or less axisymmetrical. Consequently, once late infall ends, a massive disc can gradually evolve from a disc with spirals in the continuum into one featuring multiple, potentially lopsided bright rings in the continuum. In near-infrared scattered light, the disc initially displays multiple spirals during infall or shortly after it ceases, before ultimately exhibiting multiple rings. The persistent excitation of spirals implies, however, that the residual line-of-sight velocity, derived from line emission, shows large-scale spirals across the disc.
Comments15 pages, 9 figures, submitted to The Open Journal of Astrophysics
