Interstellar turbulence driven by the magnetorotational instability
Interstellar turbulence driven by the magnetorotational instability
复制标题
磁旋转不稳定性驱动的星际湍流
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
G. Rüdiger
中科院分区：
文献类型：
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作者：
N. Dziourkevitch;D. Elstner;G. Rüdiger
研究了垂直分层星系盘中磁旋转不稳定性的发生。在圆柱形计算域中，用ZEUSMP程序对三维非线性磁流体动力学进行了数值模拟。由于MRI的演变，产生了平均磁场的环形和极向分量。结果也适用于非常年轻的星系，假设拥有强大的磁场已经经过几个10 - 8年。的MRI增长率的剪切强度的依赖性。速度色散随高度增加，并达到约5 k m s −1，与观测结果非常一致，接近Sellwood & Balbus（1999）的预测。对于强磁场，MRI被抑制，但它不被最初存在于盘中的湍流抑制。
The occurrence of the magnetorotational instability (MRI) in vertically stratified galactic disks is considered. Global 3D nonlinear MHD simulations with the ZEUSMP code are performed in a cylindric computational domain. Due to the evo- lution of the MRI toroidal and poloidal components of the mean magnetic fields are generated. The results are also applied to very young galaxies which are assumed to possess strong magnetic fields already after a few 10 8 years. The dependence of MRI growth rate on the shear strength is shown. The velocity dispersion grows with height and reaches values of about 5k m s −1 in good agreement with observations and close to the predictions of Sellwood & Balbus (1999). For strong magnetic fields the MRI is suppressed but it is not suppressed by turbulence initially present in the disk.