太阳大气中的光球亮点

首先是对太阳光球亮点近年来研究工作的总结。光球亮点是一种发生在太阳光球上宁静区域的的小尺度和短寿命增亮现象,平均直径在100～300knm之间,平均寿命约为几分钟。光球亮点的研究对于光球辐射和磁场性质的认识具有重要意义。过去的观测显示,绝大多数光球亮点的产生和演化与磁场,特别是光球上的小尺度磁场的演化密切相关,比如,两个同极性磁场的合并,或者反极性磁场的对消,或者一个同极性磁场的分裂,均可以促使光球亮点产生或消失。基于这样的观测结果,统计研究了2722个光球亮点(1600A)与光球上偶极磁元的关系,发现大约有1/3的光球亮点出现在偶极磁元中心附近。

Magnetic Bright Points in the Solar Atmosphere

We firstly review the recent findings about the Magnetic Bright points(MBPs) on the Sun.MBPs are small-scale and short-lived structures with enhanced brightness on the solar photosphere.They have a mean diameter ranging from 100 to 300 km,and a mean lifetime of several minutes.MBPs are highly dynamic.Most of the MBPs are related to the magnetic field,especially the small-scale field in the lower solar atmosphere.MBPs are frequently observed at the region with a strong field,especially in the line of sight(LOS) strong field,i.e.up to kilogauss.Therefore,lots of magnetic energy should be stored in the MBPs.To study the MBPs is important for us to understand the progress of the radiation from the photosphere and the nature of the solar magnetic fields.Meanwhile,MBPs are thought to produce the MHD waves contributing to the coronal heating.Previous observations show that the MBPs are related to the small-scale field evolution on the photosphere, such as the coalescence of the same-polarity,the cancelation of the opposite-polarities,or the fragmentation of one magnetic field.Based on this concept,we statistically study 2722 MBPs at 1600 A from the SDO observations and the corresponding bipolar fields,and find that about 1/3 MBPs are related to the magnetic bipolar fields,indicating the cancelation of the opposite-polarities is one of the important mechanisms to produce the MBPs.