Abstract : Intense and brief bursts of X-ray emissions have been measured during the stepping process
of both natural cloud-to-ground (CG) and rocket-triggered lightning flashes. In this paper, we investigate
theoretically the energy spectra of X-rays produced by the bremsstrahlung emission of thermal runaway
electrons accelerated in the inhomogeneous electric field produced around lightning leader tips. The X-ray
energy spectrum depends on the physical properties of the associated lightning leaders. Consequently,
X-ray measurements can be used for diagnostics of the electrical properties of lightning stepped leaders.
We report simulation results of the photon energy spectra produced by 5 and 10 MV negative CG lightning
discharges that would be measured from the ground using ideal detectors. We also quantify theoretically
the radial dependence of X-ray energy spectra received at ground level during the leader stepping process.
Moreover, it is found that the ground radiation generated in this process is harmless to humans.
Type de document :
Article dans une revue
Geophysical Research Letters, American Geophysical Union, 2014, 41, pp.7406-7412. 〈10.1002/2014GL061163〉
https://hal-insu.archives-ouvertes.fr/insu-01174373
Contributeur : Nathalie Pothier
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Soumis le : jeudi 9 juillet 2015 - 09:35:53
Dernière modification le : jeudi 7 février 2019 - 15:24:18
Document(s) archivé(s) le : mercredi 26 avril 2017 - 01:30:06
Wei Xu, Sebastien Celestin, Victor P. Pasko. Modeling of X-ray emissions produced by stepping lightning leaders. Geophysical Research Letters, American Geophysical Union, 2014, 41, pp.7406-7412. 〈10.1002/2014GL061163〉. 〈insu-01174373〉
