Upper panel: radial velocity measurements for HD 50169, plotted against orbital phase. The solid curve corresponds to the orbital solution given in Sect. 5. The time T₀ of periastron passage is adopted as phase origin. Bottom panel: plot of the differences O − C between the observed values of the radial velocity and the predicted values computed from the orbital solution. The dotted lines correspond to ±1 rms deviation of the observational data about the orbital solution (dashed line). Open triangles (dark violet) represent data from Carrier et al. (2002) and asterisks (turquoise) ESO CASPEC observations from Mathys & Hubrig (1997) and Mathys (2017); all other symbols have the same meaning as in Fig. 2.