Optimization of a gadolinium‐rich oxyhalide glass scintillator for gamma ray spectroscopy

A transparent gadolinium‐rich oxyhalide glass scintillator was developed for gamma ray spectroscopy with an energy resolution of 14.0% at 662 keV. To the best of our knowledge, this is the highest energy resolution reported for a glass‐based scintillator. The high gadolinium content facilitated a scintillator density of 4.4 g/cm³. The high fluorine and bromine incorporation is advantageous for better uniformity and a good light output of ~3200 Ph/MeV. The peak emission at 431 nm with a FWHM of 90 nm, resulting from the fast Ce³⁺ transitions, yielded pulse‐height spectra with distinctive peaks from 122 keV to 1.33 keV for gamma radiation from different nuclides.