由闪电放电引发的光核反应
Teruaki Enoto1, Yuuki Wada2,3, Yoshihiro Furuta2
1The Hakubi Center for Advanced Research and Department of Astronomy, Kyoto University, Kyoto 606-8302, Japan.
Nature
|November 24, 2017
概括
科学家在闪电之后观察到中子和正子, 证实了大气中的光核反应. 这项研究提供了闪电事件后的正电子产生的确证据.
科学领域:
- 大气物理
- 核天体物理学
- 高能物理
背景情况:
- 雷云作为自然粒子加速器, 产生高能马射线.
- 这些马射线可以触发光子核反应,有可能产生中子和正子.
- 之前的观察表明这些反应发生在闪电之后,
研究的目的:
- 在闪电袭击后提供中子和正子生成的确证据.
- 调查大气中的光核反应由闪电产生的玛射线.
主要方法:
- 在雷暴期间对马射线闪光的地面监测.
- 分析随后的马射线后发光和线辐射光谱.
- 检测与闪电事件相关的中子和正子信号.
主要成果:
- 一个持续数毫秒的马射线闪光被检测到,
- 在0.511兆电子伏时观察到延长的线路辐射,这表明了电子-正子灭绝.
- 观察到的信号与通过光核反应捕获中子和产生正子的预测一致.
结论:
- 在闪电发生后产生正电子的确证据.
- 这些发现证实闪电可以启动大气中的光核反应.
- 这项研究加深了我们对极端大气电气现象的理解.
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