Numerical simulations of type I planetary migration in non‐turbulent magnetized discs
Numerical simulations of type I planetary migration in non‐turbulent magnetized discs
复制标题
非湍流磁化盘中 I 型行星迁移的数值模拟
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
R. Nelson
中科院分区：
文献类型：
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作者：
S. Fromang;C. Terquem;R. Nelson
利用二维磁流体动力学（MHD）数值模拟和两种不同的有限差分欧拉代码，我们分析了环形磁场对非湍流原行星盘中低质量行星迁移的影响。磁场的存在改变了可以在圆盘中传播的波。与最近的线性分析一致，我们发现两个磁共振在行星轨道的两侧发展，这有助于显著的全球扭矩。为了测量圆盘对行星施加的扭矩，我们进行了模拟，其中后者要么固定在圆形轨道上，要么允许迁移。对于一个5m +的行星，当其所在位置声速的平方与阿尔芬速度的平方之比β等于2时，我们发现当圆盘内磁场B Φ均匀时，向内迁移，当B Φ随r -1减小时，向外迁移，当B Φ随r -2减小时。这些结果与线性分析的预测一致。总的来说，我们的结果证实，即使是一个亚热稳定场也可以阻止类地行星向内迁移。
Using 2D magnetohydrodynamic (MHD) numerical simulations performed with two different finite-difference Eulerian codes, we analyse the effect that a toroidal magnetic field has on low-mass planet migration in non-turbulent protoplanetary discs. The presence of the magnetic field modifies the waves that can propagate in the disc. In agreement with a recent linear analysis, we find that two magnetic resonances develop on both sides of the planet orbit, which contribute to a significant global torque. In order to measure the torque exerted by the disc on the planet, we perform simulations in which the latter is either fixed on a circular orbit or allowed to migrate. For a 5-M ○+ planet, when the ratio β between the square of the sound speed and that of the Alfven speed at the location of the planet is equal to 2, we find inward migration when the magnetic field B Φ is uniform in the disc, reduced migration when B Φ decreases as r -1 and outward migration when B Φ decreases as r -2 . These results are in agreement with predictions from the linear analysis. Taken as a whole, our results confirm that even a subthermal stable field can stop inward migration of an earth-like planet.