The correlation between expansion speed and magnetic field in solar flare ribbons  

作　　者：XIE WenBin WANG HaiMin JING Ju BAO XingMing ZHANG HongQi 

机构地区：[1]Key Laboratory of Solar Activity,National Astronomical Observatories of China,Beijing 100012,China [2]Physics Department,New Jersey Institute of Technology,Newark,NJ07102,USA [3]Jilin Normal University,Jilin 136000,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2009年第11期1754-1759,共6页中国科学：物理学、力学、天文学（英文版）

基　　金：Supported by the National Natural Science Foundation of China (Grant Nos. 10611120338, 10473016, 10673016, and 60673158);the National Basic Research Program of China (Grant No. 2006CB806301);the Chinese Academy of Sciences (Grant No. KLCX2-YW-T04);the National Aeronautics and Space Administration of USA (Grant Nos. NNX0-7AH78G and NNX0-8AQ90G)

摘　　要：In this paper, we study the correlation between the expansion speed of two-ribbon flares and the magnetic field measured in the ribbon location, and compare such correlation for two events with different magnetic configurations. These two events are: an M1.0 flare in the quiet sun on September 12, 2000 and an X2.3 flare in Active Region NOAA 9415 on April 10, 2001. The magnetic configuration of the M1.0 flare is simple, while that of X2.3 event is complex. We have derived a power-law correlation between the ribbon expansion speed (V r) and the longitudinal magnetic field (Bz) with an empirical relationship V r = A×Bz-δ, where A is a constant and δ is the index of the power-law correlation. We have found that δ for the M1.0 flare in the simple magnetic configuration is larger than that for the X2.3 flare in the complex magnetic configuration.In this paper, we study the correlation between the expansion speed of two-ribbon flares and the magnetic field measured in the ribbon location, and compare such correlation for two events with different magnetic configurations. These two events are: an M1.0 flare in the quiet sun on September 12, 2000 and an X2.3 flare in Active Region NOAA 9415 on April 10, 2001. The magnetic configuration of the M1.0 flare is simple, while that of X2.3 event is complex. We have derived a power-law correlation between the ribbon expansion speed (V r ) and the longitudinal magnetic field (B z ) with an empirical relationship V r = A×B- z ?δ , where A is a constant and δ is the index of the power-law correlation. We have found that δ for the M1.0 flare in the simple magnetic configuration is larger than that for the X2.3 flare in the complex magnetic configuration.

关 键 词：SOLAR activity SOLAR FLARES SOLAR magnetic field 

分 类 号：P182.7[天文地球—天文学]