Performances of the LTB in imaging observations. Manifestation of the LTB at different instants in each observed band, (a) AIA 94 Å band, (b) AIA 131 Å band, (c) AIA 171 Å band, (d) AIA 1600 Å band, and (e) IRIS/SJI 1400 Å band. The ellipse in panel b3 denotes the area based on which we calculated the emission light curves (Fig. 3) and the evolution of the maximum temperature and maximum emission measure (Fig. 7). The blue curves in panels a–e show the contours of the intensity at levels of 22 DN, 80 DN, 800 DN, 200 DN, and 280 DN. The pink curves in different AIA bands correspond to the contours of the SJI 1400 Å band.