Flicker parameters as a function of the stellar surface gravity. The flicker indexes (left) have been interpolated to a fixed level of white noise (σ_w = 30 ppm) for this comparison. The flicker frequencies are shown in the right panel. In both panels, the gray dots indicate values obtained for the sample of Kepler bright targets (magnitude < 10) involved in Sulis et al. (2020a). The pentagon symbols indicate values obtained for HD 67458 and the triangle symbols for HD 88595 based on CHEOPS high-precision observations. The star symbols indicate the value obtained for the Sun (VIRGO observations). The square symbols indicate the values obtained from HD simulations of 17 stars (see Sect. 6). The color code indicates the stellar metallicity [Fe/H] (not shown for Kepler targets).