论文标题
在爆发磁通绳的足迹上研究喷发前磁性
Investigating pre-eruptive magnetic properties at the footprints of erupting magnetic flux ropes
论文作者
论文摘要
众所周知，太阳喷发是由在电晕中携带电流磁场中存储的游离磁能提供的。也普遍认为，磁通绳（MFR）是许多冠状质量弹出（CME）的关键组成部分。仍然有争议的是在喷发之前是否存在MFR。我们的目的是鉴定MFR的祖细胞，并研究与这些祖细胞相关的爆发前磁性。在这里，我们分析了从2010年到2015年，从磁盘中心45度爆发的28个MFR爆发。所有MFRS'feet均通过共轭冠状斑点很好地识别。然后，我们使用Helioseiscic和磁成像仪（HMI）矢量磁图计算MFRS脚下的磁性能。我们的结果表明，只有8个爆发的MFR与明显的非中和电流有关，其中4流也显示了脚印的爆发前凹痕。在这些MFR的两英尺处，扭曲和当前分布是不对称的。与非中和电流相关的爆发前凹陷的存在表明已存在的MFRS。此外，脚印内的共轭凹痕和电流的演变可以提供有关MFRS内部结构及其形成机制的线索。
It is well established that solar eruptions are powered by free magnetic energy stored in current-carrying magnetic field in the corona. It has also been generally accepted that magnetic flux ropes (MFRs) are a critical component of many coronal mass ejections (CMEs). What remains controversial is whether MFRs are present well before the eruption. Our aim is to identify progenitors of MFRs, and investigate pre-eruptive magnetic properties associated with these progenitors. Here we analyze 28 MFRs erupting within 45 deg from the disk center from 2010 to 2015. All MFRs'feet are well identified by conjugate coronal dimmings. We then calculate magnetic properties at the feet of the MFRs, prior to their eruptions, using Helioseismic and Magnetic Imager (HMI) vector magnetograms. Our results show that only 8 erupting MFRs are associated with significant non-neutralized electric currents, 4 of which also exhibit pre-eruptive dimmings at the foot-prints. Twist and current distributions are asymmetric at the two feet of these MFRs. The presence of pre-eruption dimmings associated with non-neutralized currents suggests the pre-existing MFRs. Furthermore, evolution of conjugate dimmings and electric currents within the foot-prints can provide clues about the internal structure of MFRs and their formation mechanism.
