摘要
本文采用NaI(Tl)探测器搭建了闪电高能辐射地面观测装置并进行了性能测试。于2016年夏季探测到1次自然负地闪过程中的两次回击之前产生的γ射线爆发信号,这是国内首次获得自然闪电高能辐射的实测波形数据。第1次γ射线爆发持续时间为563μs,第2次γ射线爆发持续时间为353μs,两次γ射线爆发的截止时间间隔为76.288ms,与同步观测到的回击电场波形时间间隔一致。经分析发现,梯级先导的负脉冲信号与高能辐射的脉冲信号具有一一对应的特征,表明梯级先导是本次测量所获闪电高能辐射的产生根源。
By using a NaI(Tl)detector,a lightning high energy radiation ground observation system was set up in this paper,and a performance test was conducted.In summer of 2016,two bursts of γ-rays were recorded at ground level for the first time in China when the return strokes of a nearby negative cloud-to-ground lightning flash occurred.The first γ-ray burst has a duration of 563μs and the second one has a duration of 353μs.The time interval between the end time of the two bursts is 76.288 ms,and this is coincident with the time interval of return strokes revealed by the synchronous electric field signal.The analysis result shows that the signals from the stepped leader and the γ-ray have one to one correspondence,and the stepped leader of the light-ning is the source of the high energy radiation.
引文
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