arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1411.2736astro-ph.EPastro-ph.SR
收藏

原行星盘中的间隙、环和非轴对称结构--从模拟到ALMA观测

Gaps, Rings, and Non-Axisymmetric Structures in Protoplanetary Disks - From Simulations to ALMA Observations

M. Flock, J. P. Ruge, N. Dzyurkevich, Th. Henning, H. Klahr, S. Wolf

备注：
Language update, added comments, added citations, in press. (A&A)
发表信息：
A&A 574, A68 (2015)
阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

摘要：

阿塔卡马大型毫米/亚毫米阵列（ALMA）最近对年轻恒星周围的圆盘进行的观测揭示了尘埃连续辐射的明显不对称性。在这项工作中，我们要研究轴对称和非轴对称结构，诱发的磁旋转不稳定性的外部区域的原行星盘。我们结合国家的最先进的数值模拟的结果与后处理辐射转移（RT）生成合成地图和预测ALMA。我们进行了非理想的全球三维MHD分层模拟的死区外缘使用FARGO MHD代码PLUTO。恒星和磁盘的参数是从一个参数化的磁盘模型适用于拟合高角分辨率多波长观测的拱星磁盘。从给定的表面密度分布和Monte-Carlo辐射转移一致地计算2D温度和密度分布。使用粉尘化学模型计算2D欧姆电阻率分布。磁场是垂直净通量场。由此产生的尘埃再发射提供了ALMA观测模拟的基础。基准模型开发了一个大的差距，然后在位于死区外边缘的表面密度的跳跃。密度和压力的跳跃足以阻止粒子的径向漂移。此外，我们观察到的Rossby波不稳定性（RWI）的跳跃位置接近60 AU的涡的产生。涡旋以40个局部轨道的周期稳定地产生和破坏。RT结果和模拟ALMA观测预测了在没有行星的情况下观测出现在磁化盘中的这种大尺度结构的可行性。

英文摘要：

Recent observations by the Atacama Large Millimeter/submillimeter Array (ALMA) of disks around young stars revealed distinct asymmetries in the dust continuum emission. In this work we want to study axisymmetric and non-axisymmetric structures, evocated by the magneto-rotational instability in the outer regions of protoplanetary disks. We combine the results of state-of-the-art numerical simulations with post-processing radiative transfer (RT) to generate synthetic maps and predictions for ALMA. We performed non-ideal global 3D MHD stratified simulations of the dead-zone outer edge using the FARGO MHD code PLUTO. The stellar and disk parameters are taken from a parameterized disk model applied for fitting high-angular resolution multi-wavelength observations of circumstellar disks. The 2D temperature and density profiles are calculated consistently from a given surface density profile and Monte-Carlo radiative transfer. The 2D Ohmic resistivity profile is calculated using a dust chemistry model. The magnetic field is a vertical net flux field. The resulting dust reemission provides the basis for the simulation of observations with ALMA. The fiducial model develops a large gap followed by a jump in surface density located at the dead-zone outer edge. The jump in density and pressure is strong enough to stop the radial drift of particles. In addition, we observe the generation of vortices by the Rossby wave instability (RWI) at the jumps location close to 60 AU. The vortices are steadily generated and destroyed at a cycle of 40 local orbits. The RT results and simulated ALMA observations predict the feasibility to observe such large scale structures appearing in magnetized disks without having a planet.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

↑