MUSE synthetic line profiles for Fe IX, Fe XV and Fe XIX emission line, as a function of height, z, slit number, and Doppler shift velocity, as seen in Fig. 5. The spectral bins here are Δv = 25 km s⁻¹ for Fe IX, Δv = 30 km s⁻¹ for Fe XV, and Δv = 40 km s⁻¹ for Fe XIX. The angular pixel along z is 0.4″, equivalent to 290 km (see Appendix A) for Fe IX and Fe XV lines and 2.7″ for Fe XIX. The positions of the profiles shown in Fig. 10 are marked (circle, diamond and star).