Variation along the slit of the cross-correlation function (CCF, first and third columns) from fxcor and the [S iii] λ9069 line profile (second and fourth columns). The leftmost two columns show the results for slit ℬ and the rightmost columns the results for slit . Where the CCF peak value is smaller than 0.25 or the Paschen subtraction is deemed unreliable, the CCF is shown in grey. The emission-line profiles have been continuum-subtracted. Each sub-panel is labelled with the position of the extraction window, where the origin is set to the position where the two slits cross (see Fig. 1). Knot ℬ is at position +1.̋9 along slit ℬ, and knots and are at −2.̋2 and + 3′′ along slit , respectively.