论文标题
磁重新连接事件对磁盘湍流中能量耗散的贡献
Contribution of Magnetic Reconnection Events to Energy Dissipation in Magnetosheath Turbulence
论文作者
论文摘要
通过分析MMS的磁盘测量值,我们获得了磁重新连接(MR)事件在电子尺度上对相干结构的能量耗散的贡献的统计结果。使用增量(PVI)方法的部分方差用于在磁场数据中找到相干结构。进一步选择了具有磁场成分逆转的当前纸结构。我们考虑以下标准以识别MR事件,例如具有磁场逆转,明显的能量耗散和明显的电子流速度的当前表。从统计上讲,对于大多数MR事件,它们的PVI值大于其他类型的相干结构的值,并且它们的能量耗散也比其他类型的结构更强。但是,由于MR事件的比例相对较小,因此它们对相干结构耗散的贡献相对微不足道。如果考虑到非辅助结构的耗散,则MR对耗能的贡献将较小。因此,我们建议MR事件虽然在局部存在强大的耗散,但并不是导致磁石中能量耗散的主要贡献者。在分析了非MR电流表的特征之后,我们提出非MR电流板主要是动力学alfvén波动固有的连贯结构。
By analyzing the magnetosheath measurements from MMS, we obtain the statistical results for the contribution of magnetic reconnection (MR) events at electron scales to the energy dissipation of coherent structures. The Partial Variance of Increments (PVI) method is employed to find coherent structures in the magnetic field data. The current sheet structures with reversal of magnetic field components are further selected. We consider the following criteria to identify the MR events, such as current sheet with magnetic field reversal, significant energy dissipation, and evident electron outflow velocity. Statistically, for most MR events, their PVI values are larger than that of other types of coherent structures, and their energy dissipations are also stronger than that of others. However, due to the relatively small proportion of MR events, their contribution to coherent structures' energy dissipation is relatively trivial. If taken into account the dissipation of non-coherent structures, the MR's contribution to energy dissipation would be less. Hence, we suggest that MR events, though have strong dissipation locally, are not the major contributor to the energy dissipation in the magnetosheath. After analyzing the features of non-MR current sheets, we propose that non-MR current sheets are mainly coherent structures inherent to kinetic Alfvén fluctuations.