太阳射电分米波毫秒级尖峰辐射的寿命

Duration of the Solar Radio Spike Radiation at Decimetric Waves and Milliseconds

太阳射电毫秒级尖峰辐射的寿命随频率增高而减小,长期以来这一直是个令人困惑的问题。本文从与Ⅲ型爆发相关的空心束分布的电子流所激发的回旋同步脉泽角度出发,详细讨论了尖峰辐射的寿命与特征频率比(ξ=ω_P/ω_B)以及波增长率的关系,最后得出:在分米波的不同波段,尖峰辐射是X模的不同次谐波,且寿命随频率增高发生相关的减小。

The duration of the solar radio millisecond spike radiation is shortened with the increase in the frequency,which has been a puzzling problem for a long time.In this paper,according to the electron cyclotron maser excited by the electron beams of the hollow beam distribution associated with the type Ⅲ bursts,the relation between the duration of the spike radiation and the characteristic frequency ratio(i.e.the parameter = ψp /ψB)with the wave growth rate is discussed in detail.Finally,it is concluded that at the different wavelengths of the decimetric wave,the spike radiations are the different frequency harmonic waves and the correlative decrease of the duration appears with the increase in the frequency.