THE CORONAL STRUCTURE OF AB DORADUS
THE CORONAL STRUCTURE OF AB DORADUS
复制标题
剑鱼座的冠状结构
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
T. Gombosi
中科院分区：
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作者：
O. Cohen;J. Drake;V. Kashyap;G. Hussain;T. Gombosi
我们使用全球磁流体动力学（MHD）模型对年轻的快速旋转的K 0矮星剑鱼座AB的日冕进行了数值模拟。该模型是由一个表面地图的径向磁场构造使用塞曼多普勒成像。我们发现，恒星日冕的全球结构是由强烈的方位角纠缠的磁场由于快速旋转。MHD解使我们能够计算出真实的阿尔文曲面，因此我们可以估计恒星的质量损失率和角动量损失率，而无需进行过度的理论简化。我们考虑三种情况下，参数化的基础密度的电晕，跨越系统的可能的解决方案的范围。我们发现，总的来说，质量和角动量的损失率比太阳的情况要高;质量损失率高出10-500倍，角动量损失率可以比现在的太阳值高出3 × 104。我们的模拟表明，该模型可以用来约束恒星系统的宽参数空间。它还表明，MHD方法可以提供更多的信息，物理系统比常用的位场外推。
We perform a numerical simulation of the corona of the young, rapidly rotating K0 dwarf AB Doradus using a global magnetohydrodynamic (MHD) model. The model is driven by a surface map of the radial magnetic field constructed using Zeeman–Doppler Imaging. We find that the global structure of the stellar corona is dominated by strong azimuthal tangling of the magnetic field due to the rapid rotation. The MHD solution enables us to calculate realistic Alfvén surfaces, and we can therefore estimate the stellar mass loss rate and angular momentum loss rate without making undue theoretical simplifications. We consider three cases, parameterized by the base density of the corona, that span the range of possible solutions for the system. We find that overall the mass and angular momentum loss rates are higher than in the solar case; the mass loss rates are 10–500 times higher, and the angular momentum loss rate can be up to 3 × 104 higher than present-day solar values. Our simulations show that this model can be used to constrain the wide parameter space of stellar systems. It also shows that an MHD approach can provide more information about the physical system over the commonly used potential field extrapolation.