Position velocity diagrams (PVDs) extracted from the H I cube along the three 1.25′ wide right ascension slices indicated in the top right corner. The Hα emission convolved with the H I PSF is shown in orange. For reference, the red contour in the middle panel represents the stellar velocities extracted from Bellhouse et al. (2017) (no convolution to the HI angular resolution was performed). The Hα contours are drawn at surface brightness levels of 1 × 10ⁿ erg s⁻¹ cm² where n = −10, −9, −8 ⋯. The blue contours are the H I emission from the cube drawn at flux densities of 0.3, 0.4, 0.5 ... mJy beam⁻¹ and the negative H I contours are drawn at −0.3, −0.2 ... mJy beam⁻¹. The vertical dashed line is the systemic velocity of the galaxy and the horizontal line is the optical centre. Velocities in the PVDs are in the optical definition using the barycentric standard-of-rest.