Spectral momentum method in collisional-radiative modeling of plasmas
The spectrum momentum method for calculation of emission spectra of nonstationary non-equilibrium collisional-radiative plasma is developed. The intensity of radiation is expanded in a series of basic functions that are dependent on the photon energy, dependent on the resonance structure of the cross sections, and provide a fast convergence of the expansion (in the range of several harmonics). The expansion coefficients – «spectral momentums» are calculated by solving the kinetic equation for the Lebesgue photons distribution. This distribution and cross sections of the kinetic equation are Lebesgue integrals of the original spectral distribution and non-monotonic cross sections on the system of Lebesgue sets. Fast convergence of the expansion is shown in a series of test problems.