SPECTROSCOPIC ANALYSIS OF PROTON-INDUCED FLUORESCENCE FROM CERIUM-DOPED YTTRIUM-ALUMINUM-GARNET

We have determined the effect of proton induced damage on relative sci ntillation efficiency for yttrium aluminum garnet doped with cerium (Y AG: Ce). The YAG: Ce phosphor samples were exposed to a 3 MeV proton b eam, and substrate temperature was limited to control heating damage. Real time in situ measurements of the fluorescence spectra permitted o bservation of the spectral characteristics of scintillator deteriorati on due to particle induced damage. Fluorescence from YAG: Ce is relati vely dim when compared to other rare earth oxysulfide compounds and th e light intensity drops rapidly with dose. Spectra from proton irradia ted YAG: Ce exhibit a broad fluorescence peak that is much wider than is typical in other yttrium and gadolinium phosphor compounds. The phy sical processes in YAG:Ce are very different from other bright-line ph osphors as shown by the large difference in the observed fluorescence peak width. Light intensity decreases with dose, following the Birks a nd Black empirical model.