a) Hα line profiles (green solid lines) of V351 Ori of a few days in December 2008. Synthetic Hα  line profiles (blue dashed lines) are overplotted on each spectrum. Modified Julian days are displayed against the respective spectrum. The vertical red dashed line represents the rest frame velocity of the star. b) Residual spectra of Hα line profiles in the same epochs. Horizontal blue dashed lines represent the zero absorption levels. (This figure is available in colour in electronic form.)