Mean burst profile of the structure of the P3 feature in the three observations. The upper panel is relative to G-3 data in the energy range [9.1–15.1] keV. The blue line defines the constant level used for computing the excess and statistical errors in each bin (0.5 s width) are reported, the dashed line is the linear extrapolation of the last two bins along the P3 profile. In the lower panel profiles relative to G-1 and G-2 are shown, with the energy ranges corresponding to the five highest energy channels: [8.6–13.0] and [7.8–12.9] keV, respectively.