Radioluminescence pumping

Studies of some optical materials, like fluored glass, crystals or polymers, show an important luminescence in the visible spectrum, near UV, due to high energy radiation (α, β, n, X-rays or γ). This phenomenon, known as radioluminescence or scintillation, is especially used for medical physics and dosimetry. Those materials can be doped by heavy metal ions, like rare-earth elements. Recent studies show that the irradiation of such rare-earth doped scintillators, can emit visible spectral rays. Those are corresponding to rare-earth transitions, in addition to the normal radioluminescence of the undoped material. Those peaks cannot correspond to the propagation of the self-trapped exciton in the inorganic scintillator. We actually believe the rare-earth ions are just excited by the light (blue) emitted by the scintillator, and that finally this phenomenon is not electronic but photonic, thus a kind of radioluminofluorescence.