Evaluation of scintillation properties of Mg4(Ta,Nb)2O9 single crystals

Mg4(Ta,Nb)2O9 single crystals were synthesized by the floating zone method, and the photoluminescence and scintillation properties were evaluated. Under X-ray irradiation, Mg4Ta2O9 single crystal showed an emission peak at 350 nm, while Nb-contained ones showed an emission peak at 400 nm. The decay curves were approximated by one exponential decay function, which indicated the decay time in μs order. Among the samples, Mg4Ta1.5Nb0.5O9 showed the highest light yield of 22,000 ph/MeV and the lowest afterglow levels of ∼10 ppm. •We have synthesized Mg4(Ta,Nb)2O9 single crystals by floating zone method.•We have characterized the photoluminescence, scintillation, and dosimetric properties.•Ta-contained compositions showed luminescence properties due to the charge transfer from Ta5+ to O2− and oxygen vacancies.•Nb-contained compositions showed luminescence properties derived from the octahedral NbO6 group.•Mg4Ta1·5Nb0·5O9 and Mg4Ta1·0Nb1·0O9 single crystals showed higher light yield than those of practical dense scintillators such as BGO.