Magnetohydrodynamics of Protoplanetary Disks

AST-0908269 Stone该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。该项目将调查原行星盘的气体动力学，以及盘与行星的相互作用。 这些工作包括：（1）通过原行星盘中的磁旋转不稳定性（MRI）研究角动量传输;（2）研究盘-行星相互作用激发的密度波的传播、衰减和间隙打开;以及（3）研究原行星盘的完全全球模型，可以研究盘在广泛半径范围内的结构和演化。 原行星盘的现实模型是具有挑战性的，因为必须包括各种各样的物理学，这些计算将是最复杂的尝试。 这些模拟将通过整合从现实尺寸分布中提取的数百万个颗粒的运动，遵循与气体动力学自洽的尘埃颗粒在盘中的湍流混合和沉降。 要添加的效果是在晶粒上的重组，作为12种非平衡电离和重组网络的一部分，所有相关的非理想磁流体动力学（MHD）过程，以及辐射扩散和光学薄冷却，以遵循气体的热力学。 所有必要的代码元素都已在Athena中实现和测试，Athena是一种新的强大的基于网格的天体物理MHD代码。 研究结果将是最真实和最精确的原行星盘非理想磁流体动力学模型，以及对行星形成环境和行星与盘相互作用的深入了解。该项目包括培训研究生，以及将结果向更广泛的公众传播的动画和可视化。 该团队通过普林斯顿大学夏季本科生研究计划，积极参与理论和计算天体物理学中的女性和代表性不足的群体。 这项工作继续促进部门间和国际合作，通过开放源码软件理念向天体物理学界提供雅典娜代码。

AST-0908269StoneThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).This project will investigate the gas dynamics of protoplanetary disks, and the interaction of disks with planets. The work includes (1) studies of angular momentum transport by the magnetorotational instability (MRI) in protoplanetary disks, (2) studies of the propagation and damping of, and gap opening by, density waves excited by disk-planet interaction, and (3) fully global models of protoplanetary disks that can investigate the structure and evolution of disks over a wide range of radii. Realistic models of protoplanetary disks are challenging because of the diverse range of physics that must be included, and these calculations will be the most sophisticated yet attempted. These simulations will follow the turbulent mixing and settling of dust grains in the disk self-consistently with the gas dynamics by integrating the motion of millions of particles drawn from a realistic size distribution. Effects to be added are recombination on grains, as part of a twelve-species non-equilibrium ionization and recombination network, all of the relevant non-ideal magnetohydrodynamic (MHD) processes, and radiative diffusion and optically thin cooling to follow the thermodynamics of the gas. All of the necessary code elements have been implemented and tested within Athena, a new and powerful grid-based code for astrophysical MHD. The result should be the most realistic and accurate models of the non-ideal MHD of protoplanetary disks possible, and a deep understanding of the environment of planet formation and the interaction of planets with the disk.The project includes training of graduate students, and animations and visualizations for dissemination of the results to the wider public. The team is vigorously engaged in involving women and under-represented groups in theoretical and computational astrophysics through a Princeton summer undergraduate research program. The work continues to foster interdepartmental and international collaboration by providing access to the Athena code to the astrophysics community through an open-source software philosophy.