Line-of-sight velocity in km s⁻¹ calculated from the Hα narrow line vs the radial distance from the centre of nucleus A in pixels. The pixel scale is 0.123 arcsec per pixel. Overplotted is the intensity profile of the Hα narrow line. The black dashed line represents the intensity = 0 level for the Hα line. The zero of the x-axis represents the point of highest intensity of the Hα narrow line. The dashed green line represents the stellar velocity field derived from our simulations explained in Sect. 5.3.2.