“…Scintillators convert ionizing radiation into visible-UV photons, and they have been widely utilized to measure ionizing radiation in the fields of security, (1) medical imaging, (2,3) and resource exploration. (4,5) In general, required properties of scintillators include high scintillation output, short decay time, high energy resolution, and high effective atomic number; however, since no materials currently satisfy the requirements of all applications, R&D has been performed continuously on scintillators in various forms such as single crystals, (6)(7)(8)(9)(10)(11) ceramics, (12)(13)(14) films, (15,16) glasses, (17)(18)(19)(20)(21)(22)(23) and liquids. (24)(25)(26) Our research has focused on rare-earth-activated alkali-earth aluminates, which have been intensely studied in phosphor fields (27)(28)(29) ; in particular, Eu,Dy-co-doped SrAl 2 O 4 is a wellknown long-lifetime phosphorescent material.…”