Performances of the spectrum. The spectral data in the five main windows of the IRIS at 02:35:00 UT (a–e) and 02:35:56 UT (f–j). The former was obtained at the position of raster 7, and the latter was obtained at the position of raster 5. The lines on which we focus in each panel are C II 1334.53/1335.71 Å (a, f), Fe XXI 1354.08 Å (b, g), Si IV 1402.77 Å (c, h), and Mg II k&h 2796.35/2803.52 Å (d&e, i&j). The white curve in each panel shows the intensity profile obtained at the site denoted by the short white bar in panels a and f.