Spectral momentum method in collisional-radiative modeling of plasmas

The spectrum momentum method, simplifying the calculations of multiresonance emission spectra of non-equilibrium collisional 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 convergence of the expansion in the range of several harmonics. Efficient way of finding the expansion coefficients — "spectral moments" — based on the solution of the kinetic equation for the Lebesgue distribution of photons is described. Fast convergence of the expansion is shown.