论文标题
3D MHD模拟在具有倾斜磁性和旋转轴的恒星上的增生模拟
3D MHD Simulations of Accretion onto Stars with Tilted Magnetic and Rotational Axes
论文作者
论文摘要
我们介绍了对磁化恒星的积聚的全局三维（3D）磁性水力学（MHD）模拟的结果，其中恒星的磁轴和旋转轴都围绕圆盘的旋转轴倾斜。我们观察到，由于磁层和盘之间的磁相互作用，盘的内部部分是旋转，倾斜和过程的。后来，较大的倾斜盘形成，尺寸随恒星的磁矩增加而增加。从5-10度到30-40度的不同角度将圆盘的正常矢量倾斜。小倾斜可能是由于磁场线在恒星旋转轴周围的绕组以及倾向于对齐盘的磁力的作用而产生的。另一个可能的解释是磁性bardeen-petterson效应，在该效应中，由于盘中的前液和粘性扭矩，圆盘在恒星的赤道平面中沉降。在参考半径（大约3个恒星半径）处，倾斜的圆盘缓慢地，以50个开普勒周期的时间尺度缓慢进度。我们的结果可以应用于不同类型的恒星，其中已经观察到倾斜盘子和/或缓慢进动的迹象。
We present results of global three-dimensional (3D) magnetohydrodynamic (MHD) simulations of accretion onto magnetized stars where both the magnetic and rotational axes of the star are tilted about the rotational axis of the disc. We observed that initially the inner parts of the disc are warped, tilted, and process due to the magnetic interaction between the magnetosphere and the disc. Later, larger tilted discs form with the size increasing with the magnetic moment of the star. The normal vector to the discs are tilted at different angles, from 5-10 degrees up to 30-40 degrees. Small tilts may result from the winding of the magnetic field lines about the rotational axis of the star and the action of the magnetic force which tends to align the disc. Another possible explanation is the magnetic Bardeen-Petterson effect in which the disc settles in the equatorial plane of the star due to precessional and viscous torques in the disc. Tilted discs slowly precess with the time scale of the order of 50 Keplerian periods at the reference radius (approx. 3 stellar radii). Our results can be applied to different types of stars where signs of tilted discs and/or slow precession have been observed.
