Collisional-radiative modeling of the 2p3l(l = p,d) spectra of N II and application to lightning

The excitation energies, transition rates, collisional-excitation cross sections, and collisional-excitation rate coefficients of N II ions have been calculated by the relativistic configuration-interaction method with the implementation of the flexible atomic code. The population rate coefficients were subsequently investigated and shown that the net population rate coefficients of the 2p3d configuration are greater than those of the 2p3p configuration at an identical electron temperature. A reasonable collisional-radiative model has been constructed to simulate the 2p3s–2p3p and 2p3p–2p3d spectra, which were in reasonable agreement with the lightning data presently obtained in experimental measurements. A further application was implemented in effectively determining the lightning parameters, with the aid of a certain area surrounded by the intersections of contours of multiple line-intensity ratios on the two-dimensional plane of electron temperature and electron density.