标题： 具有改进的三维辐射流体力学的引力不稳定原行星盘中的质量和角动量输运 显示英文标题

标题： Mass and Angular Momentum Transport in a Gravitationally Unstable Protoplanetary Disk with Improved 3D Radiative Hydrodynamics

摘要： 在原行星盘早期阶段，引力不稳定性可以产生显著的质量传输，极大地改变盘的结构，并混合和冲击处理气体与固体，可能在行星形成中起重要作用。 我们展示了一个基于三维网格的辐射流体力学研究，该研究针对一个环绕一颗0.5 M$_\odot$恒星运行、质量为0.07 M$_\odot$的原行星盘的不同分辨率模型。当盘在其大部分半径范围内达到准稳态渐近状态时，该状态在由引力不稳定性产生的加热与由真实尘埃消光系数决定的辐射冷却之间维持近似平衡。 我们评估了盘的稳定性标准、热动力学性质、引力不稳定性强度、由引力不稳定性产生的密度波和扭矩特性、这些扭矩引起的径向质量传输以及这种传输能在多大程度上被表示为局部或非局部过程。 物理和热力学过程在盘内光学厚区域和外光学薄区域之间显示出明显的差异。 在内区，引力扭矩主要由方位角质量分布的低阶傅里叶分量主导。 这些扭矩在局部动力学时间尺度上变化剧烈，且受快速爆发的影响，这种爆发可能是由反复的摆动放大驱动的。 在外区，m=1 扭矩占主导地位。 环状结构表现出强烈的非圆周运动，并在8到14天文单位之间的内缘附近发展出漩涡。 我们发现，在整个低-Q部分的盘中，引力不稳定性引发的螺旋模式以混乱的方式爆发，许多螺旋模式出现又消失，产生重力湍流，但主要由波动的大规模模式主导，这与简单的$\alpha$盘截然不同。 显示英文摘要

摘要： During early phases of a protoplanetary disks's life, gravitational instabilities can produce significant mass transport, can dramatically alter disk structure, can mix and shock-process gas and solids, and may be instrumental in planet formation. We present a 3D grid-based radiative hydrodynamics study with varied resolutions of a 0.07 M$_\odot$ disk orbiting a 0.5 M$_\odot$ star as it settles over most of its radial extent into a quasi-steady asymptotic state that maintains approximate balance between heating produced by GIs and radiative cooling governed by realistic dust opacities. We assess disk stability criteria, thermodynamic properties, strengths of GIs, characteristics of density waves and torques produced by GIs, radial mass transport arising from these torques, and the level to which transport can be represented as local or nonlocal processes. Physical and thermal processes display distinct differences between inner optically thick and outer optically thin regions of the disk. In the inner region, gravitational torques are dominated by low-order Fourier components of the azimuthal mass distribution. These torques are strongly variable on the local dynamical time and are subject to rapid flaring presumably driven by recurrent swing amplification. In the outer region, m=1 torques dominate. Ring-like structures exhibiting strong noncircular motions, and vortices develop near the inner edge between 8 and 14 au. We find that GI-induced spiral modes erupt in a chaotic manner over the whole low-Q part of the disk, with many spiral modes appearing and disappearing, producing gravitoturbulence, but dominated by fluctuating large-scale modes, very different from a simple $\alpha$-disk.