Left panel: example of cross-correlation function (black line) and its Gaussian fit (red thick line). Right panel: zoom in on the maximum of the cross-correlation function and its parabolic fit (red thick line). We first used a Gaussian fit to locate the position of the maximum and then defined a smaller velocity range (Gaussian fit FWHM) and computed the cross-correlation function over a finer grid to improve the determination of the radial velocity.