Simulation of the CB RV effect of an equatorial 1% spot (top) and 1% facula (bottom) for different temperature of the quiet photosphere (i.e., different spectral type) using the PHOENIX spectral library. The temperature difference between the quiet photosphere ∆T_eff for spot and facula. is fixed to 663 and 250 K, respectively. Due to the strong absorption effect of molecules in spots on stars cooler than the Sun, we see the appearance of a flux effect in the derivation for the CB effect only (see Sect. 4.3.3).