太阳耀斑的高分辨观测研究

The study on solar flares has lasted for many years. Up to now, it is still the key and difficult point in the research of solar physics. One meter solar tower in Chengjiang Fuxian Lake has solar photospheric and chromospheric observation with high resolution, bringing a good opportunity for us to study solar flares in detail. Our research focuses on the following aspects: (1) at the early stage of the flare eruption, analyzing the fine variation of the photosphere and chromosphere, the change characteristics of the corona, and the physical reasons, to explore the energy source and trigger mechanism of flares, providing the basis for the forecast of solar flares; (2) in the process of the flare eruption, investigating the energy release process of flares i.e.,the formation of the current sheet and the energy dissipation,through the analysis of the high resolution observational characteristics of chromosphere and corona; (3) analyzing the relationship between the evolution characteristics of the post-flare loops formed at the later stage of the flare and the change of the magnetic field topology.

太阳耀斑的研究已经持续了很多年了,目前依然是太阳物理研究的重点和难点。澄江抚仙湖一米太阳塔具有高分辨率的光球和色球观测,为我们更精细的研究太阳耀斑带来了良好的机会。我们的研究主要集中在以下几个方面:(1)耀斑爆发前期,分析光球、色球的精细变化及日冕的变化特征及其物理原因,探求耀斑的能量来源及触发机制,为预报太阳耀斑提供依据;(2)耀斑爆发过程中,通过对色球和日冕的高分辨率观测分析,研究耀斑的能量释放过程,即电流片的形成及能量耗散;(3)研究耀斑后期形成的耀斑后环的演化特征及其与磁场拓扑结构变化的关系。

太阳耀斑是剧烈太阳爆发活动之一，是灾害性空间天气的源头，研究其爆发前兆、触发机制等对预报灾害性空间天气有非常重要的意义。该项目主要集中在太阳耀斑爆发的能量来源及其爆发前兆，耀斑爆发过程中光球、色球、日冕磁场拓扑结构的演化、耀斑后环的演化特征及其拓扑结构变化等研究上，在该项目支持下共发表SCI论文12篇。该项目主要数据来源于云南天文台一米新真空望远镜和空间SDO卫星观测数据，同时结合势场外推和非线性无立场外推等方法。通过对多个太阳耀斑爆发的研究，发现磁流浮现、磁场剪切、黑子旋转运动往往出现在太阳耀斑爆发之前，随着这些光球层的运动在高层大气会形成扭缠的爆发磁结构，也会存在扭缠的磁绳浮现爆发产生太阳耀斑。通过运用非线性无立场外推能够得到三维磁场结构，可以计算出耀斑爆发前储存的能量，从而可以粗略估算耀斑级别的大小。太阳耀斑爆发的产生往往是爆发磁结构与新浮现的磁场或者进一步的光球剪切运动导致的。这些研究结果对于将来构建更加完善的太阳耀斑爆发模型和更加准确预报灾害性空间天气提供了很好的观测依据。