Parameter diagnosis for the plasma of artificially triggered lightning based on collisional-radiative model.

Based on the collisional-radiative model, the energy levels, transition rates, andcollision excitation rate coefficient of N II ions were calculated by implementingthe Flexible Atomic Code. The line intensity of characteristic spectral lines for NII ions was simulated, which shows that the variations of electron temperature andelectron density can affect the simulation of line intensity. In addition, the plasmaspectra for an artificially triggered lightning, derived from Guangdong, China,were adopted to be simulated. It is found that when the simulated spectrum is wellmatched with the experimental one, its plasma environment becomes as 32,000 Kand 1017 cm−3, which is called Visual-Spectra-Matching (VSM) method. Moreover, through adopting the Multi-Spectra-Ratio-Matching (MSRM) method, theresults are diagnosed as 32,000±103 K and (1.38±0.6)×1017cm−3. Good agreements can be found in the comparisons among VSM, MSRM, and other measurements.