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Title: Energetic Radiation from Subsequent-Stroke Leaders: The Role of Reduced Air Density in Decayed Lightning Channels
Leaders of subsequent strokes in negative cloud-to-ground lightning are known to produce X-ray/gamma-ray emissions detectable at distances of a few kilometers or less from the lightning channel. These leaders usually develop in decayed but still warm channels of preceding strokes. We computed electric field waveforms at different points along the path of subsequent leader as those points are traversed by the leader tip. For a typical subsequent leader, the electric field peak is a few MV/m, which is sufficient for production of energetic radiation in a warm (reduced air density) channel. We examined the dependence of electric field peak on the leader model input parameters, including the prospective return-stroke peak current (a proxy for the leader tip potential) and leader propagation speed, and compared model predictions with measurements.  more » « less
Award ID(s):
2114471
PAR ID:
10415022
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Applied Sciences
Volume:
12
Issue:
15
ISSN:
2076-3417
Page Range / eLocation ID:
7520
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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