Growth, thermo-stability and radiation damage of cerium-doped lanthanum chloride (LaCl3:Ce) scintillation crystal

LaCl3:5%Ce crystals with diameter of 25 mm were grown by modified non-vacuum Bridgman method. Their photo-luminescence at temperature from 80 to 500 K in steps of 50 K were measured by the single-photon counting method with FLS920 spectrofluorimeter. It was found that the total emission intensity above room temperature is little stronger than that below room temperature. And the decay times also show slight increase with temperature. Irradiation with γ-ray from 60Co source will induce some optical absorption within 320–500 nm in the crystals, cause decrease of light yield and change the relative intensity ratio of the two emissions from 5d→2F5/2 and 5d→2F7/2, but have no influence on the luminescence mechanism.