Density dependence of the line emission of boron-like coronal ions

Assuming steady state conditions, the authors have calculated the occupation of 20 levels of the ion Si X as a function of the electron density and temperature taking into account collisional processes and spontaneous radiative ones. Between the two levels of the ground state also the photoabsorption of the corresponding infrared radiation has been considered. The emission of the most important UV-,X- and IR-lines is determined as a function of the electron density and temperature. Intensity ratios are plotted versus electron density. The line emission as a function of the height of the radiating layers is studied for UV- and X-ray lines. The resulting fluxes in earth distance are compared with observations. (Auth.)