Analysis of the coronal source of the partially limb-occulted flare on 2002 July 20  

作　　者：Jin-Hua Shen Victor Melnikov Tuan-Hui Zhou Hai-Sheng Ji 

机构地区：[1]Key Laboratory for Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences [2]Graduate University of Chinese Academy of Sciences [3]Central Astronomical Observatory at Pulkovo, Russian Academy of Sciences

出　　处：《Research in Astronomy and Astrophysics》2013年第8期961-977,共17页天文和天体物理学研究（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant Nos. 11111120071, 10833007, 11173062, 11221063 and 11178002);the National Basic Research Program of China (973 Program, 2011CB811402);supported by the Chinese Academy of Sciences visiting professorship for senior international scientists (Grant No. 2010t2j36);by the joint RFBR-CNSF (Grant No. 11-02-91175)

摘　　要：We carry out a detailed analysis of the X3.5 solar flare that occurred on 2002 July 20, which is the strongest partially limb-occulted flare ever observed by the RHESSI satellite. The main results are： （1） during the main impulsive phase that lasts ,-10 minutes, the motion of the thermal sources follows a U-shaped trajectory. Nonthermal sources move in a similar way, but in a series of larger zigzags. We further show that the non-thermal sources are actually leading the contraction motion. （2） During the main impulsive phase, X-ray sources at different energies continuously form a loop-like configuration, with the highest energy source （up to ,- 100 keV） and the lowest energy source （down to ,- 10 keV） being located at two ends. The entire loop-like configuration moves in a U-shaped trajectory, while keeping the order of descending energy from highest to lowest during motion. Two non-thermal hard X- ray sources with different energies are spatially well separated in the distribution. The unusual complexities of the X-ray emissions in the tenuous solar corona challenge interpretations using bremsstrahlung in a simple magnetic configuration.We carry out a detailed analysis of the X3.5 solar flare that occurred on 2002 July 20, which is the strongest partially limb-occulted flare ever observed by the RHESSI satellite. The main results are： （1） during the main impulsive phase that lasts ,-10 minutes, the motion of the thermal sources follows a U-shaped trajectory. Nonthermal sources move in a similar way, but in a series of larger zigzags. We further show that the non-thermal sources are actually leading the contraction motion. （2） During the main impulsive phase, X-ray sources at different energies continuously form a loop-like configuration, with the highest energy source （up to ,- 100 keV） and the lowest energy source （down to ,- 10 keV） being located at two ends. The entire loop-like configuration moves in a U-shaped trajectory, while keeping the order of descending energy from highest to lowest during motion. Two non-thermal hard X- ray sources with different energies are spatially well separated in the distribution. The unusual complexities of the X-ray emissions in the tenuous solar corona challenge interpretations using bremsstrahlung in a simple magnetic configuration.

关 键 词：SUN activity - Sun X-ray - Sun FLARES 

分 类 号：P182.52[天文地球—天文学] P182.62