Variation of aquoluminescence during the decay and regeneration of thermoluminescence under F-light

A kinetic study of the room temperature decay of thermoluminescence (TL) and aquoluminescence (AL) from γ-irradiated alkali halides showed the decay to be complex consisting of a series of monomolecular terms : I = λ1A1 exp (— λ1t) + λ2A2 exp (— λ2t) + • • • Decay periods of the components are determined for NaCl, NaBr, KC1, KBr, KI, NH4C1, NH4Br, SrCl2 and BaCl2. Exposure of a crystal, from which TL has nearly wholly decayed, to F-light of even feeble intensity regenerates a second cycle (TL.-II) which decays similarly. Corresponding changes occur in the AL producible. The existence of an intermediate energy level of relatively longer life is postulated to explain the regeneration of TL by F-light