1. College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070, China 2. Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000,China 3. Thunder Prevention and Observation Center of Shanxi Province, Taiyuan 030002, China
Abstract：Spectra of return strokes for artificial triggered lightning were obtained by optical multi-channel analyzer (OMA) in Shandong region. Compared with previous spectra of natural lightning, additional lines of ArⅠ 602.5 nm and ArⅡ 666.5 nm were observed. Under the model of local thermodynamic equilibrium, electronic temperatures of the lightning channel plasma were obtained according to the relative line intensities. Meanwhile, with semi-empirical method the electron density was obtained by Hα line Stark broadening. In combination with plasma theory, electrical conductivity of the lightning channel has been calculated for the first time, and the characteristic of conductivity for lightning channel was also discussed. The relation between the electrical conductivity of channel and the return stroke current was analyzed, providing reference data for further work on computing return stroke current. Results show that the lightning channel is a good conductor, and electrons are the main carrier of channel current. The brightness of artificial triggered lightning channel is usually higher than that of natural lightning, and its current is smaller than that of the natural lightning.
Key words：Electrical conductivity;Electron temperature;Electron density
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