HESS J1303−631 spectrum derived using an integration region of radius 0.6°. The spectrum is well fit with a power-law function with spectral index Γ = 1.5 ± 0.2 with a fitted cutoff energy of E_cut = (7.7 ± 2.2) TeV. The fit resulted in a χ²/N.D.F. of (20/8) corresponding to 1% p-value. A fit of a power-law spectrum with no cutoff, shown by the dashed line, resulted in a p-value of 7 × 10^-8. The last spectrum point deviates  ~2σ from the fitted curve. It was removed from the residuals plot for better visibility.