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Time-resolved spectra of the luminescence in oxygen-deficient α-Al 2 O 3 crystals were studied using synchrotron radiation. The UV luminescence with hν = 3.26 eV and τ = 1.6 ns was detected in addition to the known slowly relaxing component (hν = 3 eV, τ = 34 ms) of the emission transition of the F-center under excitation near 6 eV. It is observed only at T ≤ 80 K in spectra, which are measured using the orientation of the polarized excitation light approaching E⊥C 3 . Three bands at 5.28, 5.90 and 6.41 eV are discernible in the time-resolved spectrum of the luminescence (hν = 3.26 eV) excitation at T = 8 K.