On the electric field at the tip of dart leaders in lightning flashes |
| |
| Authors: | Vernon Cooray Marley Becerra Vladimir Rakov |
| |
| Institution: | 1. Division for Electricity and Lightning Research, Ångström Laboratory, University of Uppsala, Box 534, SE 751 21, Uppsala, Sweden;2. Department of Electrical and Computer Engineering, University of Florida, Gainesville, USA;1. Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands;2. Tractebel Engineering S.A, Avenue Ariane 7, 1200 Brussels, Belgium;1. Atmospheric Physics and Lightning Research Group, Department of Physics, University of Colombo, Colombo 3, Sri Lanka;2. Lightning Research Group, The Ångström Laboratory, Division of Electricity, Department of Engineering Sciences, Uppsala University, Box 534, SE-751 21, Uppsala, Sweden |
| |
| Abstract: | The results obtained in this study show that as the dart leader tip passes a given point on the defunct return stroke channel the electric field increases within a fraction of a microsecond to values larger than the critical electric field necessary for the initiation of cold electron runaway in low-density air comprising the channel. These results are in support of the hypothesis that cold runaway electron breakdown may play a role in the emission of X-ray bursts by dart leaders. The calculations also show that the peak power dissipated by a typical dart leader is about 300–500 MW/m and the energy dissipated within the first 10 μs or so is about 500–600 J/m. Furthermore, the minimum resistance and the maximum radius of the core of a typical dart leader are estimated to be about 3 Ω/m and 0.003 m, respectively. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
