一个微波爆发的源区磁场和高能电子的能流估计

本文分析了１９９３年１０月２日０７：３９：４０－０７：４１：００ＵＴ时段太阳产生的一个多脉冲微波暴的观测，认为它是由多个脉冲爆发叠加在一个慢变爆发背景上组成的．根据谱分析和利用我们的日冕磁场诊断公式［１］，第一次获得了一个爆发源区的磁场强度和高能电子的信息，其主要结果是：（１）脉冲爆发分量在光薄部分的射电谱指数的平均值比慢变爆发背景的值小１，即前者的谱比后者的硬．在１９．６ＧＨｚ上的亮度温度前者比后者高６倍．（２）从脉冲爆发分量和慢变爆发背景分量推断的源区磁场平均值分别为１５８和５３１高斯，且发现在爆发期间，慢变暴源区磁场强度随时间圣马鞍形变化，在极大相的值比脉冲相和下降相低约５０％（３）产生脉冲暴分量的高能电子的柱密度ＮＬ和数密度Ｎ（＞Ｅ０）分别为慢变暴分量的４％和８％，但它们所携带的能流和发射系数要比慢变爆发分量的值高１倍和８倍！表明这两种爆发成份可能分别来自能谱不同的两群电子在不同爆发源区的辐射．

MAGNETIC FIELD STRENGTH AND ENERGY FLUX OF ENERGETIC ELECTRONS IN A MICROWAVE BURST SOURCE REGION

The observation of a microwave burst With multiple impulses occurred on Oct. 2,1993 between 07. 39. 40-07 f 41:00UT was analysed. We think this impulsive event maybe composed of multiple impulse components superimposing on a slow burst background. Based on the spectral analyses the magnetic field strength and information forhigh energy electrons were obained for the first time by using our formula forcoronal magnetic field diagnostic. These Results are as follows:1. The average spetral index of the impulsive burst compenents at the opticallythin part is 1 less than that of theslow burst background, ie, the former spectrum isharder than that of the latter on an average. The average brightness tempefature ofthe impulsive burst components at 19.6Gz frequency is 6 times higher than that ofthe slow burst.2. On an average the magnetic field strengths are, respectively, 158 and 531Gauss in the impulsive burst region and the slow burst one derived from the spectrralanalysis. We find that the variatio of the magnetic field strength B with bine displayes horse's saddle shape in the slow burst source region' The value of B inmaximun phase is about 50% lower than that of the impulse phase or the deCay one.3. Collunm density NL and number density N of high energy electrons which prerduce the impulsive burst component are 4% and 8% of the slow burst one,respectively, but their energy flux and emission coefficient are 1 time and 8 timeshigher than that of the slow burst. It was shown that the two burst emmissions areproduced by two eletron groups with different energy distribution which come fromtwo fifferent source regions.