Lomb-Scargle periodogram of the HARPS radial velocity datasets and activity indicators from K2-32 (left panels) and K2-233 (right panels). For each system we show, from top to bottom, the periodogram corresponding to: the radial velocity, the residuals after subtracting the radial velocity model (for K2-233 we also show the residuals of the GP model) and the 1 and 0.1% false alarm probabilities as horizontal dotted lines, the full-width at half maximum of the cross-correlation function and the bisector span. The planet periods are marked as dotted lines and the rotation period of K2-233 and its first harmonic are marked as dashed lines.