Long GRBs, time-resolved analysis. Top panel: distributions of the characteristic energies (E_beak and E_peak for the 2SBPL (blue and red hatched histogram, respectively) and E_peak for the SBPL model (black empty histogram). Gaussian functions showing the central value and standard deviation for each distribution are overplotted to the histograms (with the same colour-coding). Bottom panel: E_peak versus E_break scatter plot (2SBPL model). The equality line is shown with a solid line.