ZONES OF HIGH IONIZATION OF GAS IN NUCLEI OF SEYFERT-GALAXIES AND QUASARS

On the basis of the V. V. Sobolev's probability method, we calculate relative line intensities and level populations of hydrogen and He II for a broad range of physical parameters [N(e)(H) = 10(9-11) cm-3, T(e) = (2-3).10(4) K, velocity gradients in the gas dV/dR = 10(-4- -6) s-1] under the assumption that the stationary population of levels is due to a simultaneous action of shock and radiative mechanisms of gas heating and ionization. It is accepted that the central source of radiation is nonthermal: F(nu) = F0 (nu/nu0)-alpha with F0 = 10(-5) erg.cm-2.s-1.Hz-1 with various spectral indices alpha = 0-1. On the basis of a comparison of the calculated and observed relative intensities of hydrogen and He II lines, physical parameters are estimated for the regions of formation of high-excitation lines, located above the accretion disc surface: N(e) = 10(11) cm-3, T(e) = 3.10(4) K, dV/dR = 10(-5) s-1.