Airmass (top) and sum of the radial (stellar) and barycentric velocities (bottom) for each exposure during the first observing night with CARMENES. In this analysis, we discarded seven exposures with airmass higher than 1.6 to reduce the effects of contamination by the telluric features. The dashed lines represent the times of first, second, third, and fourth contact. This figure can be compared with Fig. B.1.