Magnetic Reconnection Rate in the M6.5 Solar Flare on 2015 June 22
Magnetic Reconnection Rate in the M6.5 Solar Flare on 2015 June 22
复制标题
DOI：
10.3847/1538-4357/accf9f
复制
发表时间：
2023-06
期刊：
影响因子：
--
通讯作者：
Bryce Cannon;J. Jing;Qin Li;Nian Liu;Jeongwoo Lee;W. Cao;Haimin Wang
中科院分区：
文献类型：
--
作者：
Bryce Cannon;J. Jing;Qin Li;Nian Liu;Jeongwoo Lee;W. Cao;Haimin Wang
磁重联被认为是太阳耀斑期间活动区中储存的磁能快速释放的机制，磁重联率的定量测量对于理解太阳耀斑至关重要。在标准双带耀斑模型的背景下，我们推导了2015年6月22日M6.5耀斑的日冕磁场重联率，重联通量变化率和重联电场，这两个项都可以从耀斑形态的观测中获得。使用的数据包括大熊太阳观测站古德太阳望远镜（GST）的视觉成像光谱仪在耀斑期间以前所未有的分辨率拍摄的一系列色球Hα图像，以及GST近红外成像光谱偏振仪沿着的耀斑前视线光球磁图和拉马迪高能太阳光谱成像仪的硬X射线数据。磁重联率和非热辐射之间的时间相关性被发现，和重联电场的变化主要是由带的速度，而不是由所遇到的带前的局部磁场。在空间上，硬X射线源与同时获得的最强电场的位置重叠。带状运动显示出丰富的精细结构，包括在具有较弱磁场的光桥位置处的局部加速度。
Magnetic reconnection is regarded as the mechanism for the rapid release of magnetic energy stored in active regions during solar flares, and quantitative measurements of the magnetic reconnection rate are essential for understanding solar flares. In the context of the standard two-ribbon flare model, we derive the coronal magnetic reconnection rate of the M6.5 flare on 2015 June 22 in two terms, reconnection flux change rate and reconnection electric field, both of which can be obtained from observations of the flare morphology. Data used include a sequence of chromospheric Hα images with unprecedented resolution during the flare from the Visual Imaging Spectrometer of the Goode Solar Telescope (GST) at the Big Bear Solar Observatory and a preflare line-of-sight photospheric magnetogram from the GST Near-InfraRed Imaging Spectropolarimeter along with hard X-ray data from the Ramaty High Energy Solar Spectroscopic Imager. The temporal correlation between the magnetic reconnection rate and nonthermal emission is found, and the variation of the reconnection electric field is mainly determined by the ribbon speed, not by the local magnetic field encountered by the ribbon front. Spatially, the hard X-ray source overlaps with the location of the strongest electric field obtained at the same time. The ribbon motion shows abundant fine structures, including a local acceleration at the location of a light bridge with a weaker magnetic field.