论文标题
光球融合运动在启动太阳喷发中的作用
The role of photospheric converging motion in initiation of solar eruptions
论文作者
论文摘要
众所周知，主要的太阳喷发通常是由具有持续光谱剪切和收敛运动的活动区域产生的。在这里，通过高精度磁流失动力学模拟，我们展示了如何以第一次剪切驱动的单个双极构型启动太阳喷发，然后在底部表面收敛运动。与以前的许多模拟不同，我们在没有磁扩散的情况下应用了收敛运动，因此它仅增加了跨极性反转线的磁梯度，但没有取消磁通量。剪切街机的脚关节运动的融合运动以准静态方式创建了当前纸，并且喷发是由当前纸的磁重新连接触发的，该磁盘的磁重新连接支持了与以前的模拟相同的场景，仅剪切运动。通过收敛的运动，当电流板以较低的高度形成，并且电流密度比单独的剪切运动更高，这使得重新连接更有效，更强烈。此外，融合运动使高度的上层衰减速率具有快速的衰减速率，因此有利于喷发。这表明，与仅通过剪切流相比，融合流量更有效地创建当前纸张，对喷发更有利。
It is well known that major solar eruptions are often produced by active regions with continual photospheric shearing and converging motions. Here, through high accuracy magnetohydrodynamics simulation, we show how solar eruption is initiated in a single bipolar configuration as driven by first shearing and then converging motions at the bottom surface. Different from many previous simulations, we applied the converging motion without magnetic diffusion, thus it only increases the magnetic gradient across the polarity inversion line but without magnetic flux cancellation. The converging motion at the footpoints of the sheared arcade creates a current sheet in a quasi-static way, and the eruption is triggered by magnetic reconnection of the current sheet, which supports the same scenario as shown in our previous simulation with only shearing motion. With the converging motion, the current sheet is formed at a lower height and has a higher current density than with shearing motion alone, which makes reconnection more effective and eruption stronger. Moreover, the converging motion renders a fast decay rate of the overlying field with height and thus favorable for an eruption. This demonstrate that the converging flow is more efficient to create the current sheet and more favorable for eruption than by solely the shearing flow.
