THE OPTICALLY THICK Fe XVII SPECTRUM: X-RAY, EXTREME-ULTRAVIOLET, AND FORBIDDEN LINE RATIOS

摘要

Level populations, X-ray line fluxes, and extreme-ultraviolet (EUV) line intensities are calculated for a 37 level model of the Fe XVII ion, as functions of the column density of Fe XVII, in slab geometry and cylindrical geometry. The resonance lines at 15.02 and 15.25 A are found to exhibit initial increases in fluxes relative to the forbidden line at 17.10 A and the usual reference resonance line at 16.78 A as optical thickness increases. Eleven EUV lines and the forbidden 2p~53s(~3P_o-~3p_1) transition near 1154 A are also found to be relatively enhanced by opacity.