Mass detection limits for hypothetical companions with P = 1 yr that induce an RV amplitude three times larger than the activity-jitter rms derived from the high-cadence observations, plotted vs. host star (spectroscopic) T_eff. Ages are coded in colour. Stars marked as triangles do not have a significant IR excess (see Sect. 3.1). The horizontal dashed-dotted line marks the approximate boundary between the low-mass stellar and substellar regimes and the dashed line marks the approximate boundary between the planetary and brown-dwarf mass regimes. The dotted line marks 3 MJup.