Left: spectral energy distributions of the synthetic burst GRB_B010 and local photon index in the four time intervals [0 s, 1 s], [1 s, 3 s], [3 s, 6 s] and [0 s, 6 s]. Right: multi-detector light curves of GRB_B010: summed counts in two energy ranges of GBM/NaI detectors (first two panels), in the GBM/BGO energy range (third panel) and using the largest LAT energy range (> 30 MeV) (bottom panel). The red dashed lines show the boundaries of the three time intervals [0 s, 1 s], [1 s, 3 s] and [3 s, 6 s].