Investigation of the influence of the reabsorption of radiation in spectral lines on the gain coefficient on transitions of Li-like ions in a recombining laser plasma

A detailed self-consistent model of the population kinetics of the levels of aluminum ions is developed with consideration of the gas dynamics of the plasma and radiation transfer. It is used to analyze the experimental results and to investigate the accuracy of describing the reabsorption of radiation in spectral lines within the Sobolev approximation. It is shown that for locally optically thick lines the photon-escape-probability approximation is in satisfactory agreement with the results of a numerical solution of a combined system of equations describing the kinetics and resonant radiation transfer in an inhomogeneous moving plasma