Examples of 17 Mg II k slit spectra in the scan of raster 5 covering the prominence. The top left image is a slit jaw image, the vertical dashed-dotted lines indicate the FOV of the raster, and the thin dashed line the position of the slit S42 at 12:48 UTC used to draw the profiles in Appendix C. In Figs. C.1 and C.2 and in the bottom spectra, a series of green and blue lines indicate the position of these profiles along the slit for positions A1–12 and B1–16, respectively.