对澳大利亚Culgoora天文台射电频谱仪在太阳活动第23周峰年期间记录到的米波Ⅲ型爆发(20-420MHz),与日冕物质抛射(CME)、Hα耀斑及相关事件进行了统计分析,发现米波Ⅲ型爆发与CME的关系没有Ⅱ、Ⅳ型爆发与CME的关系密切;米波Ⅲ型爆发发生的时间在CME之前25-30min最多;72%的CME事件伴随长寿命的Hα耀斑.从这些观测特征出发,对米波Ⅲ型爆发、CME和Hα耀斑进行了定性的解释.
Statistical analyses of the correlation events between the type Ⅲ radio bursts and Coronal Mass Ejections (CMEs) during 23rd cycle are presented, radio data were observed with the 20-420 MHz at the Radio Spectrograph Culgoora Solar Observatory in Australia. It is found that the relation between the decimetric type Ⅲ bursts and CMEs is not closer than the relation between the type Ⅱ radio bursts and CMEs. Most of metric type Ⅲ radio bursts occurred 25-30 min before CME, and about 72% CMEs events correlated with gradual flares. Meanwhile, the higher energy of theflare corresponds to the larger initial velocity of the correlated CMEs. As for impulsive flares, the type Ⅲ bursts are produced probably owing to the ejection of high energy electronic beam from the open magnetic line of force. And around the electronic beam and along the open magnetic line of force there simultaneously ejects a plasma block mass, which just form a small-scale CME. In this way, the type Ⅲ burst and CME occur in the same flare. As for gradual flare, a prominence is formed possibly owing to the uninterrupted upward floatation of the magnetic flux tube in the flare. The ejection matter of the prominence produces the large-scale CME, but on the edge of the magnetic flux loop there exists the open magnetic field line, the energetic electronic beam can eject and produce type Ⅲ bursts.