论文标题
通过快速磁重新连接对Tokamak电流轮廓扁平,对太阳电晕的影响
Flattening of the tokamak current profile by a fast magnetic reconnection with implications for the solar corona
论文作者
论文摘要
在托卡马克(Tokamak)中断期间,观察到净平行电流的轮廓是在时间尺度上扁平的,以至于必须是由于快速磁重新连接所致。快速磁重连接的磁性表面破裂后,单个磁场线覆盖了整个体积,而不仅仅是磁性表面。当前轮廓,由$ k \equivμ_0J_{||}/b $给出,在该体积内部放松到沿混乱的磁场线传播的alfvén波在该体积中放松。这种放松的时间尺度决定了当前尖峰的普遍观察到的破坏现象,并且血浆内部电感突然下降。得出了一种研究这种放松的有效方法,可以更好地理解当前尖峰中编码的信息以及血浆内部电感的突然下降。还讨论了对冠状加热的影响。
During tokamak disruptions the profile of the net parallel current is observed to flatten on a time scale that is so fast that it must be due to a fast magnetic reconnection. After a fast magnetic reconnection has broken magnetic surfaces, a single magnetic field line covers an entire volume and not just a magnetic surface. The current profile, given by $K\equivμ_0j_{||}/B$, relaxes to a constant within that volume by Alfvén waves propagating along the chaotic magnetic field lines. The time scale for this relaxation determines the commonly observed disruption phenomena of a current spike and a sudden drop in the plasma internal inductance. An efficient method for studying this relaxation is derived, which allows a better understanding of the information encoded in the current spike and the associated sudden drop in the plasma internal inductance. Implications for coronal heating are also discussed.