Results of the frequency analysis of Sc II 5239 Å line in the spectra of 20 CVn by means of the pixel-by-pixel method. The two panels represent the original data (left) and the simulated data set characterized by S/N of 40 (right). Each panel illustrates the mean profile (top), and the amplitude and phase across this profile (middle and bottom, respectively). The solid and dashed lines represent the original observed and the LSD-based model spectra, respectively. The corresponding error margins are shown by the bars. The results are shown for the dominant (radial) mode of ~8.22 d^-1 (95.11 μHz).