Simulated emission lines from a flat circumstellar disk using the toy disk model. The grey lines show the continuum-subtracted average Ca II line detected in HD 152384, whereas the green lines show the model with the parameters i = 24° (corresponding to the stellar inclination), α = 1.0, R_in = 0.03 au, and R_out = 0.15 au (corresponding to the best fit parameters). In each panel the red and blue lines illustrate the effect of varying one model parameter (top left: inclination; top right: α; bottom left: disk inner radius in au; bottom right: disk outer radius in au).