Magnetohydrodynamic and electromagnetic-particle simulations on the spontaneous fast magnetic reconnection model

我们提出了自发快速重联模型，并通过精确的计算机模拟研究了它的基本物理机制。在各种物理情况下已经明确证明，由于重联区(微观)异常电阻率与全球重联流之间的正反馈，包括驻留慢激波在内的快速重联机制可以急剧演化，因此自发的快速重联演化被认为是长电流片系统的非线性不稳定。结果表明，这一理论模型直接导致了环顶前方有快速激波的大尺度磁环的形成，同时也形成了大尺度的等离子体团并向外传播。最近，仿真模型被扩展到三维，并阐明了自发快速重联模型的详细三维特征。

We have proposed the spontaneous fast reconnection model, and its basic physical mechanism has been studied by precise computer simulations. It has been definitely demonstrated in a variety of physical situations that the fast reconnection mechanism involving standing slow shocks can drastically evolve because of the positive feedback between the (microscopic) anomalous resistivity in the reconnection region and the global reconnection flow, so that the spontaneous fast reconnection evolution is considered to be a nonlinear instability of the long current sheet system. It is shown that a large-scale magnetic loop formation with a fast shock standing just ahead of the loop top directly results from this theoretical model ; also, a large-scale plasmoid is formed and propagates outwards. Recently, the simulation models are extended to three dimensions, and the detailed 3D features of the spontaneous fast reconnection model have been clarified.