Modeling of X-ray emissions produced by stepping lightning leaders
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.
Origin : Publisher files allowed on an open archive
Loading...