Fig. 11. Observed and reconstructed trailed spectra of H for the individual nights (April 18 and 19 (top), April 20 and May 29 (middle), May 30 and 31 (bottom) for left to right, respectively). For each night, two images of the observed (left) and reconstructed (right) spectra are arranged side by side. The vertical axis corresponds to the photometric phase. The rotational disturbance is removed for the reconstructed spectra, i.e., spectra of the phase 0.1-0.8 were used for the mapping (-0.9 were also excluded as a preventive measure). The horizontal axis represents the velocity ( cm s^-1).