Doppler maps of the Hα emission. From left to right the different maps correspond to the pre-eruption, eruption, and post-eruption epochs. For each epoch, the top panel illustrates the map with contours corresponding to 95 (magenta), 80 (blue), 65 (cyan), 50 (green), 35 (yellow), and 20% (red) of the value of the highest peak in the map. The black dot corresponds to the orbital motion of the Be star with K_Be = 4.3 km s⁻¹. The bottom panel illustrates the same map as a colour plot.