Theory of ball lightning

H. -C. Wu

doi:10.1038/srep28263

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arXiv · 1411.4784

Theory of ball lightning

H. -C. Wu

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Abstract

We present a comprehensive theory on the formation of ball lightning, a luminous sphere sometimes observed after normal lightning. In a ball lightning event, a relativistic electron bunch can be produced by the stepped leader of lightning and coherently emit high-power microwave when striking the ground. The intense microwave ionizes the local air and evacuates the resulting plasma by its radiation pressure, thereby forming a spherical plasma cavity that traps the microwave. The theory can explain observed properties of ball lightning and should be useful to lightning protection and aviation safety.

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H. -C. Wu. 2014-11-18. Theory of ball lightning. https://doi.org/10.1038/srep28263

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