Time evolution of total Si IV 1402.77 Å intensity calculated assuming optically thin plasma and for different models. Details are given in the titles of panels and the arrangement of the panels, parameters, and their units is the same as in Fig. 3. Black lines correspond to the Si 1393.75 Å line and red lines to the 1402.77 Å line. Dashed lines show total intensities calculated without density suppression of dielectronic recombination.