Left: containment interval of the relative systematic uncertainty on the LAT effective area (blue curves) as a function of the photon energy E, and the two ϵ(E) functions used to estimate the corresponding distortion effect on our spectral analysis (red curves). Right: folding energies for the time intervals c, d₁, and d₂, obtained with or without considering the systematic uncertainties on the LAT effective area. The results were superimposed onto the LAT counts light curve above 30 MeV.