Radial velocity curve of the companion star in J1727 measured through cross-correlation with the template star HD219134 (K3/4V), and folded to the best-fit ephemerides. We repeated two orbital phases for visualisation purposes. The top panel shows the individual radial velocities (blue dots), as well as the best fit sinusoid (solid red line). The best-fitting parameters are also reported in this panel. The bottom panel shows the residuals from the best fit.