Luminescence and scintillation properties of Tl- and Ce-doped Cs₂HfCl₆ crystals

The luminescence and scintillation properties of Tl- and Ce-doped Cs₂HfCl₆ crystals were investigated by photoluminescence and radioluminescence spectroscopy. In the photoluminescence spectra, emission bands of the activators were observed at 500 nm for Tl-doped Cs₂HfCl₆, and at 340 and 380 nm for Ce-doped Cs₂HfCl₆. The radioluminescence bands were observed at 405 and 430 nm for Tl- and Ce-doped Cs₂HfCl₆, respectively. Scintillation decay time constants for the Tl- and Ce-doped Cs₂HfCl₆ were smaller than those for the corresponding undoped crystals. Scintillation light yields for Tl- and Ce-doped Cs₂HfCl₆ were estimated to be 23,700 and 15,700 photons/MeV, respectively.