A comparison between the observations and the two physically different best fitting models explored in the text. The upper panels present the average CRIRES spectrum and the profile of the best fitting model. In the lower panels, the observed photo-centre offsets calculated using AMBER differential phase measurements from the baseline with the lowest noise level (D0-A1 used on the 7th of May) are shown. For each model that fits the CRIRES spectrum we over-plot the predicted signature for the selected baseline. The model signatures are smoothed to the spectral resolution of AMBER and are shown re-binned using the size of the AMBER pixels and with a finer sampling.