Radial velocity curves for six stars. The relative radial velocities v_rad,s − ⟨v_rad,s⟩ determined for each exposure are plotted as a function of MJD for five stars where the T-test failed and we suspect a variability in the radial velocity. The curves were shifted for legibility (the dashed line represents the offset). The bottom curve (star 05223082-6944147) is a star with no radial velocity variability and shown here for reference. In red: HR11, in green: HR13, in blue: HR14 (for HR13 data and HR14 data obtained at the same epoch, the green crosses are below the blue ones). Error bars are smaller than the symbols (≤ 1 km s^-1).