Strength of the cross-correlation as function of slit position and radial velocity for the three best-fit models (see Fig. 3). We detect both CO and H₂O using single-trace gas models with a S/N of 11.6 for CO and 7.7 for H₂O, and the signal from the double-trace gas model is marginally stronger with a S/N of 12.3. These cross-correlation arrays are the averages from the two central CRIRES detectors.