Description

Three regions in quantum number space can be identified. Near the continuum (region 1) for extremely large n, collisional processes dominate. When n decreases (region 2), the radiative processes dominate over the n-n transitions, but the angular momentum mixing processes are more probable. For still smaller n (region 3), the radiative processes dominate over all collisional ones. The author formulates general analytical approach based on integro-differential equation including diffusion Fokker-Planck approximation and analytical solutions and fitting formulas checked by direct numerical calculations for regions 1, 2 and the intermediate case are presented. In particular, analytical expressions for the Seaton matrix and fitting formulas for the Green’s function in radiative-collisional plasma are given. The analytical approach to kinetics of Rydberg atoms in external Planck field is formulated. Analytical dependences of the populations of Rydberg atoms near the ionization limit are also discussed.