Stelmakh O. The Characteristics of the continuous absorption processes in the stellar photospheres.

This thesis is focused on the investigation of the spectral properties of both the photoionization and photon absorption cross sections as well as on the dependences of the continuous absorption coefficient in the photospheres of the Sun-type stars on spectral, temperature and density features. Also the spectral intensities of the radiation in the continuous spectrum for these stars were calculated. The calculations of the photoionization cross section of the negativ hydrogen ion as well as the absorption one of photons by "free" electrons were performed in the frames of the basic approach which has the significant advantages in comparison with other methods. A model photoionization cross sections of the excited hydrogen atoms, which proximately take into account the influence of recombination processes, are suggested. To obtain the exact solutions of Schrodinger equation for the electron bound states in a proton screening field the two different methods are proposed. Using these solutions the dependence of the electron energy levels on the dimensionless screening parameter was investigated. The method for the discrepancies elimination in the partition function of the hydrogen atom is proposed. It makes possible to perform a self-consistent calculation of the equilibrium number density of the micro-particles in the stars photospheres taking into account the screening Coulomb interactions. The effective hydrogen photoionization cross section