GSAG:Ce scintillator: insights from yttrium admixture

). The magnitude of thermal quenching was evidenced by combination of the temperature-dependent photoluminescence decay kinetics and thermally stimulated luminescence. Excitation spectra were measured down to 30 nm in the VUV range under the synchrotron radiation at DESY to monitor the energy transfer efficiency from the host under excitation above the band gap. Results suggested that thermal ionization was not the primary reason for the low performance of the GSAG:Ce composition, and other defects related to the presence of scandium (Sc) must play a role. Furthermore, it was found that the stoichiometric GSAG host provided a noticeably higher light yield than the previously studied congruent one. This research provides valuable insights into the characteristics of GSAG:Ce scintillators.